Archive of Our Own

Chapter Text

“Seriously, this again?” Dean scoffs, staring Sam down across the table. “You want to go see Lucifer?”

Sam sighs. He is not looking forward to any of this.

It’s the apocalypse, again, part deux, or more depending on your definition. That is if what they’ve witnessed and heard about the primordial entity known as the Darkness—also goes by Amara—are true, and they might very well be since things like these very rarely go their way. Sam can’t really bring himself to regret freeing Dean of the Mark that set said destructive entity loose, and he knows just how screwed up that is.

Still, despite their newest world-ending threat, things have actually been on the up between him and his brother, and just last week they were having easy chats and singing Night Moves in the car.

But now…

“Really, Sam?“ Dean presses and Sam has to stop himself from burying his face in his hands. Here Sam is again, chipping at the mending bond between him and his brother. Here he is, leading them toward an end he thinks necessary while Dean gives him that look, the one that he’s given every time he thinks Sam is doing something stupid. Given the subject matter, Sam isn't exactly surprised by Dean’s reaction, but he has put this off for long enough, and they’re running out of options. Amara has been wreaking havoc for a while now, and it has only gotten progressively worse.

The gist of the whole thing is that Sam has started having visions, of burning bushes and his dad and, yes, Lucifer, the Devil, the one they locked back into his cage so he didn’t end the world. Are the visions anything real? Are they signs from God? Sam is still not convinced either way, but he knows they’re something, something worth pursuing. Which is why he is currently sitting at the bunker library, trying to explain it to Dean.

Sam trudges on. “I don’t want to. I really don’t. But what else is there to do? Why are you so against this?”

“Because it’s crazy. How many times do I have to say this is a horrible idea?” Dean snaps back, as expected.

“About as many times as I have to say, okay, what else do we got?” Sam counters. “Listen, I’m all ears.” Dean just stares ahead, and Sam presses, “Dean, ordinarily I’d agree with you, but I reached out to God and asked him for a way to beat the Darkness and the visions started, and ever since they’ve only gotten more specific. And, I was in the cage.”

“Yeah, with Lucifer, the biggest monster ever hatched,” Dean says, with an exasperated wave of his hands. “Fan-freaking-tastic.”

“You know, Lucifer was the biggest monster ever hatched, until you and I hatched one that’s even worse,” he reminds Dean, who falls silent.

Technically, Sam did, released the Darkness unintentionally, just like he did Lucifer all those years ago, but this hellish cycle of theirs stretches so wide Sam is not sure if who did what even really matters that much anymore.

It’s time to bring out the big guns, so Sam clears his throat, and says, “Listen, in the vision, Lucifer... touches me. And I feel... calm, like things will be all right. And that's not something I would ever come up with. That is the last thing I would ever think.”

Consciously, at least, his mind supplies, and Sam steadfastly ignores it. Dean doesn’t need to know the level of screwed-up that Sam’s dreams are and have been for years.

“Yeah, if Lucifer touched you, it would be the last thing you’d think, ever,” Dean remarks, closing his laptop and getting up to pour himself a drink. “Why would God even ask this of you? And you know what? What proof do we have that any of this is actually real?” Dean questions, but he seems like he’s considering it now.

“We don’t, not really. I know that.” Sam isn’t sure who he’s reminding here. The visions definitely seem real, and not just because he’s mostly been awake when he gets them. Where the dreams seem like a mismatch of memories or made-up fables, the visions are clearer, no matter how they still feel familiar in an entirely wrong way. With the instances building up, it’s getting harder to ignore, especially now that shit has hit the fan again so monumentally. “But even if it’s not God, it’s something, and I think we need to follow it through. I mean, Lucifer would know how God ended the Darkness. He was there. I don’t like this either, but we need to go see him. We’ve found nothing in the lore, no one else who could help, and we do need help here.”

Dean takes a hefty sip of his whiskey and Sam watches the last bits of resistance bleed off him with it. “Alright, fine. But unless we find a safe way to talk to him, we’re not going.”

“We?”

Dean glares at him and says, like he is stating the obvious, “I’m not sending you down there alone. What’d you think, Sam?”

Some of the fear Sam has been carrying since he first saw Lucifer in his visions eases at that. For all that Sam is used to being annoyed at Dean’s over-protectiveness, right now he silently thinks it a blessing.

Maybe this won’t be quite as difficult as Sam has feared.

A day later Sam has to concede that thinking any part of this wouldn’t be awful was woefully optimistic of him. Things go from inconvenient to dangerous to goddamn disastrous in the span of a day—or, more specifically, from teaming up with a demon and a witch to shit-bad luck.

Several deals are struck: Dean and Sam enlist Crowley to help them get to Lucifer, and soon find out that with the Book of the Damned, Rowena should be able to pull the Devil into some kind of a limbo and seal his powers so he can’t hurt any of them or escape. It isn’t the most secure arrangement, since Rowena and Crowley aren’t exactly known to be the most loyal, never mind that the two seem very eager to kill each other, or at least snipe about it constantly. Still, it’s the best chance they’ve got. It eases Sam’s worries a bit to know Crowley at least doesn’t want his dark overlord free and "running amok upstairs" as he puts it; Rowena is more of a wild card.

So, that’s the plan. And like an alarming amount of the plans Sam and Dean have ever come up with, it goes bad right from the get-go.

First, Rowena insists the ritual to spring Lucifer must be conducted while her ingredients are still fresh, and since one of them blooms quite irregularly, it apparently means that night or they’ll have to wait months. Sam travels to Hell with her and Crowley, and Dean agrees to meet them there, looking into sightings of what could be the Darkness having committed a massacre in a church in a nearby town. They separate, and that’s mistake number one, right there.

Hours later, Rowena’s sigils have been drawn and all preparations are done, and Dean is nowhere to be found.

Crowley says he can’t find him anywhere in town, and Sam has a sinking feeling that it must be connected to the Darkness. Crowley claims he’ll go and grab Dean the moment he reappears, but Sam isn’t too hopeful about that happening in time. The ritual, however, must be done now, and so Sam agrees to face the Devil with only the King of Hell and a self-serving witch beside him.

It’s mistake number two, and Sam’s gnawing feeling of things ending up like this is proven right. Cas is MIA, again, and it isn’t that he doesn’t trust Dean, or want him to be there as support, but when push comes to shove, it often tends to shove him and his brother apart. Such is their life.

Rowena starts her incantation, fire erupts around the make-shift cage Lucifer is supposed to appear in, and the stone walls begin to shake around them. Sam leaves Crowley and Rowena on the front lines, retreating behind a nearby pillar in the hopes of Dean or Cas appearing at the last second. Then the ground starts rumbling, and Sam tries his best to control his breath, fighting off the instinct to run before it’s too late.

That thought is halted, however, as the rumbling ceases and he hears an all too familiar voice break the eerie quiet.

“Now this is a surprise.”

The silence that follows is deafening. It’s like all of Hell quiets in reverence to its Lord, every rotten soul and block of fire and brimstone silent to hear his every word, and Sam can feel the immense power of it in the icy pinpricks of fear traveling down his spine.

He has known that power.

Intimately.

“My old friend Crowley,” Lucifer greets the demon, contempt laced around his smooth voice.

“A mere acolyte, carrying your torch,” Crowley answers, somehow managing to sound smug even as he is facing his master, egotistical as always.

Lucifer lets out a sinister chuckle. “You're too kind. To yourself. What do you want of me?”

Sam’s feet have been locked into place since the moment he heard Lucifer’s voice, and he draws a deep breath to ground himself for what he needs to do. He knows any further stalling would only be delaying the inevitable, so instead of making Crowley scramble for an answer Sam rips the band-aid and steps out, towards the cage, and faces Lucifer.

The first thing Sam sees is a wicked smile, a match for the playful cruelty in Lucifer’s voice. Like this, Lucifer looks more like what Sam remembers of his hallucinations after the cage than of Armageddon.

Either way, it’s all wrong, too easy. It’s a character in a children’s book, a scene in a grotesque movie, a metaphor in a Zeppelin song. It’s everything you would expect from the Devil, tied together with that sinister smile.

Once Lucifer’s gaze falls on Sam, however, it’s as if the whole façade just… cracks.

“Sam…” The Devil breathes out his name, smirk bleeding away, and those piercing blue eyes of his are looking right down to his soul.

Now this is more like—

“Lucifer,” Sam chokes out through a tightness in his throat, his heart beating a tattoo in his chest.

This is the actual Lucifer he remembers, earnest and callous and poignant and so terribly real, no fabrication.

The force of the familiarity hits Sam with every single fucked up feeling that comes with having an other-worldly, celestial connection to the actual Devil. He had already felt it while hidden, the low simmering static of being this near him, all the more powerful after years away, but there is nothing shielding him from the force of it now. It has always been like this: awe, terror, delirium and need all coiled up in his sorry soul, just waiting to be set free.

This was always the worst part of Lucifer, feeling like a moth to a flame.

Except Sam has been burnt before, and still the feeling doesn’t seem to have lost its hold one bit in the process. Instead, Sam feels an urge to move closer, to reach out, and has to suppress it with an iron fist.

Lucifer, too, appears to take a solid moment to recover from surprise. He then does the most devastating thing he could at that moment and breaks out into a beatific smile. “It’s so good to see you, Sam.”

Sam’s insides twist into knots. With the way Lucifer is looking at him, he is glad Crowley has moved further away with Rowena and probably cannot see it. He would never hear the end of it.

Sam had expected anger, fury, or at the very least disdain, something to tie together their last moments together on Earth and meeting him here. But instead, there is a forever of difference between the two and something new behind Lucifer’s eyes that Sam feels like he has seen before somewhere but can't place. It should not be there in the first place; Sam is the one who put him back in the cage for crying out loud. He should look scathing, should look—

Master manipulator, he thinks someone once said, or maybe he figured that one out on his own. Regardless. He should do well to remember that.

Lucifer looks at him some more, smile fading from the edges of his face when Sam remains silent. “I’m glad you’re here, Sam. But I gotta say, I'm a little in the dark about this meeting. I don't really get visitors.” The way Lucifer says it, it could almost sound like an accusation, if the notion wasn’t so ludicrous.

Sam shrugs away the thought and answers, mustering the emptiest tone he can, “If it weren't for the crisis topside, you wouldn't be getting one now.”

The last specks of warmth on Lucifer’s face disappear at that, so quickly Sam almost suspects he imagined the whole thing. “Crisis?”

Convincing Lucifer to help them, right. That is what he has come here to do, not to analyze the Devil’s facial expressions and voice. “You're aware of the Darkness?”

Lucifer inhales sharply, which can’t mean anything good. “So, she’s really out? I sensed something big happening but wasn’t sure it was her. I’m aware of what she was, but that was eons ago.”

Sam tries to focus on Lucifer’s words and not the cadence of his smooth voice. He fixes his gaze just around Lucifer on the fake cage bars, and finds it a bit easier, not looking at Lucifer directly, though it unfortunately does nothing to quell the pull toward him. Sam’s hands clench into fists inside his pockets. “She's been released, so now she's somewhere... or everywhere on Earth. She poses a threat to all that exists, including you.”

Lucifer considers this. “Hmm. And what’s dear old dad doing?”

Sam sighs. “All current indications of his presence are… that there are no current indications of his presence.”

Lucifer makes a face, not looking all that surprised. Sam didn’t really expect him to be.

“But…” Sam begins tentatively, not sure how Lucifer is going to take hearing about what led them here. “I think he might have been reaching out,” he finally manages, trying to sound as convincing as he can. “I-I’ve been having these visions, and I think… I think they’ve been guiding me here—"

“Sam,” Lucifer interjects, and as Sam drags his gaze from the cage bars to look at him, he can see his expression is that of painful foreboding. “These visions you’re talking about, do they happen to involve me in any way?”

“Some of them,” Sam admits, an ominous pit opening in his stomach.

To Lucifer’s credit, he doesn’t burst into laughter or grin maniacally. If Sam didn’t know better, he would think the Devil’s tone is even sympathetic as he lays down the blow. “Then I’m quite sure those visions weren’t from him,” Lucifer says, sighing. “They were from me.”

“What?” Sam chokes out, though, if he is totally honest with himself, he had always known this was a possibility. What did Sam expect, something good to happen to him for once?

“Something big happened here a while ago, I guess when the Darkness descended,” Lucifer explains, and Sam can do nothing but listen as Lucifer crushes his hope. “The impact was massive, and even the cage was damaged. Through the fissures, I was able to reach out, though there was little I could control. I didn’t know if you could hear me.”

The disappointment is like an anvil coming down, and Sam has to close his eyes against the onslaught of tears. He takes a deep breath, because that is all he can really do, and smothers all his frustration and anger with experience from years and years before.

Lucifer still doesn’t display any glee at having successfully lured him here, probably playing some long game Sam isn’t aware of yet. “I’m sorry this isn’t what you were hoping for, Sam.”

That doesn’t even warrant a proper response, and Sam settles for a sarcastic, “Yeah, sure you are.” He doesn’t know what Lucifer is trying to pull with this clueless angel bullshit, when they both know better.

Lucifer just stares at him, looking puzzled and a bit peeved. “Okay, you don’t have to get all pissy about it. I didn’t mean to mislead you. I wasn’t even sure I was actually reaching you, given how weird this angel-vessel thing is. I was mostly testing the waters on the off-chance that you’d hear me and—” he cuts off, ending with a dismayed, “and something, I don’t know.”

Sam doesn’t believe a word of this, least of all the idea that Lucifer hadn’t planned this to exact detail.

He is about to say as much, when Lucifer gives him a thoughtful once-over, and continues, “But your hostility does pose an interesting question,” as he takes a step closer.

Sam knows he should have a better grip on himself than to flinch, but he doesn’t, nerves and instinct getting the better of him, and unfortunately the motion doesn’t go unnoticed. Seeing it, Lucifer pauses all movement except for a subtle incline of his head. He doesn’t move any further.

“I’ve been meaning to ask this since you showed up here. It seems a lot has happened in my absence. I mean, look at you, gaps all over,” Lucifer says, gesturing at Sam with an indecipherable look on his face. “You look like you’re mostly held together by spite and determination. What happened to you outside, Sam?”

Sam does not ask which gaps Lucifer is referring to. He is not going down that road. “A lot of things,” Sam grits out.

“Come on,” Lucifer reproaches, “You’re not gonna hold out on me now, are you? I finally see you again, after spending centuries back in this cage, and we can’t even catch up?”

Sam has had enough of this, and there is a scathing retort ready on his tongue when he hears the sound of feet on the stone floor.

“Sam!” Dean exclaims, Crowley and Cas next to him. Sam didn’t even notice he had left to fetch them.

“And the cavalry arrives,” Lucifer announces with a sigh, but Sam’s eyes are on Dean, relief flooding him. Dean looks like he’d run a mile before Crowley snatched him, but he is in one piece and that’s what counts. Cas looks less frazzled, of course, because he never looks frazzled, but Sam breathes a sigh of relief for him, too.

“Why didn’t you wait for me? Are you okay?” Dean demands, reaching Sam’s side.

“Yeah, I—sorry,” Sam says. “Rowena insisted on a tighter schedule, and you were gone for a while. It was this or a month’s wait. Where were you?”

“Meeting with Amara,” Dean replies, and makes a face at Sam’s astonishment. “Yeah. We had a lovely chat, some angels attacked her and failed, and then she zapped me back to town where Cas found me and Crowley came to get us,” Dean explains, rushed, and before Sam manages to process even a part of that Dean asks, “What’s he been saying?”

“Not much yet,” Sam says, which is as true as it is not. “You were right: the visions weren’t from God. They were from him,” he admits.

“Son of a bitch,” Dean curses, glaring at Lucifer.

“Dean Winchester. Castiel. Well, isn’t this a reunion?” Lucifer greets, demeanor shifting towards his more sardonic and cheerful persona. It’s still nothing close to the terrifying jester of Sam’s hallucinations, or the sinister tone he took with Crowley, though, so this might just be another facet of him, who knows. Sam thought he of all people knew the Devil, but from the loops this meeting has thrown Sam in already he’s not so sure anymore.

Dean doesn’t dignify Lucifer’s greeting with a reply, getting right to the point. “So, you’ve been reaching out, huh. Does this mean you wanna help us?”

Lucifer taps his fingers on his chin, thoughtful. “Well, I did help dad seal up the Darkness all those years ago, with my brothers. She's quite the force. Determined to take over everything even back then. Prone to tantrums. I can see why Pop is laying low. Now that sis is here, God's not the only circus in town.”

Now that is some actual helpful information. Maybe this visit won’t be for nothing after all.

“Is she equal to him in power?” Cas presses.

“Raw power? Sure. But she's got none of the... experience. God was a master strategist. That's why you're all here, I’ve gathered,” Lucifer says, and there’s that look again, the one Lucifer had given Sam earlier, but this time the puzzlement is laced with an odd note of dismay, and Sam is not touching that with a ten-foot pole. “You need my help to put the cat back in the bag,” Lucifer concludes.

Dean scoffs. “You can’t beat her. Last time, it took you plus three other archangels. Oh, yeah, and capital G God.”

“But you need my help, otherwise you wouldn’t be here.” There is a small pause, and Sam doesn’t need to look at Lucifer to know his eyes are on him. He then continues, “Michael and I are the only remaining archangels, and he’s currently in no condition to fight anyone. The cage has done a number on him, I’m afraid.”

Or more likely Lucifer has, Sam thinks but chooses not to argue. “And?” Sam prompts instead, quite certain he knows what’s coming next, the mental image solidifying.

“And in order to help, I have to be somewhere I actually can, not in the lowest pit of Hell. I’m pretty sure you can’t lure Amara here,” Lucifer concludes.

There it is.

It is quite ingenious of Lucifer, Sam has to admit, slithering his way into Sam’s head, knowing exactly what to show him to make him hope it is actually God calling for him, and then weaseling his way out of here by offering to help them regardless.

Dean scoffs, and Cas says what they’re all thinking. “Did you really expect us to agree to this?”

Lucifer spreads his hands. “I know, I know. But desperate times require desperate measures.”

At that, Dean finally loses his composure, roaring, “Letting you out is not desperate. It’s certifiable!”

“Okay, hold on there a second, cowboy. Take a breath. You have been working with Crowley. You passed certifiable three off-ramps ago,” Lucifer counters, defensive. “And look, I'm no fan of the ruler of the universe, but here I am, ready to pitch in.”

Sam would laugh at the sheer cosmic fuckery of it all, if he hadn’t known somewhere deep inside that it would eventually come to this. But he had, and he is still here, so maybe it says as much about him as it does the universe. “Okay, getting you out, and? What else?” Sam asks, trying to follow this diabolical thread to its conclusion in his head. It’s not too difficult.

He is proven right when Lucifer says, shrugging like it’s nothing, “Well, I do need a ride out there. I mean, I look swell in here and everything, but I'd just be a firework topside.”

Dean turns to look at Sam, a clear hell-to-the-fucking-no written on his face. Sam could take offence to his brother’s lack of trust in him, his lack of understanding of the depth of Sam’s wounds, but he’s got bigger things to worry about right now. Out of all rivaling impulses inside him amusement eventually wins, and he laughs sardonically. “So you think you’re just gonna be able to jump my bones? Again? Just like that?”

“What?” Lucifer says and has the nerve to look bewildered of all things.

Anger flares in Sam at the reaction, anger he hasn’t felt in years, and he doesn’t bother hiding it this time. “Figures. Look, I don’t care what you’ve got up your sleeve. You can taunt me, you can find a way to trap and torture me for all I care, but the answer is no and this time it will stay that way.”

Now Lucifer looks slightly alarmed, and the knot woven from these unexpected reactions only twists tighter inside Sam, irritating him to no end. “Torture? Why would you—" the Devil asks, cutting off mid-sentence, and then settles on, “Sam, you got me all wrong.”

Sam laughs, a sardonic little sound, because that is all he’s got left here. “Yeah, I doubt that.”

“Sam, I—" Lucifer begins again, but seems to read from somewhere on Sam’s face that it’s no use, because he switches gears, turning more matter of fact. “What I was getting to, is that I’ll need a vessel, if you decide to get me out. If you want me to go vessel shopping, I can do that.”

“Wait,” Dean interrupts, “You’re not goading Sam as your vessel?”

Sam is glad someone else said it; he was starting to think he might be hearing things.

“Why would I? Sam clearly doesn’t want that, like he said,” Lucifer states, like that has had any real bearing on anything ever when he has been involved. Sam looks around and judging by the looks on Dean and Cas’ faces, he is not the only one thrown by the absurdity of Lucifer’s words.

There is a beat of silence until Dean changes the subject. “Okay, but can we even get Lucifer out in the first place?”

“I can,” Rowena calls out, descending from her and Crowley’s lookout. “I will save everyone the trouble of explaining the giant loophole that’s formed here after the Darkness was released and made this possible, and just say that there is, and it has. And with the Book of the Damned, I know how to work it, no problem."

That is definitely something Rowena didn’t disclose when they embarked on this venture, but if Sam got pissed every time either the mother or son withheld information from them, he’d never know peace again, so he shrugs it off.

“Okay,” Dean says, all snark, “and what if he decides to nuke the Earth himself afterwards? You got a reverse spell in that book as well?”

Lucifer has the nerve to look peeved at the suggestion. “Relax, I’m not into that anymore. If you let me out and we beat dear Auntie, we can go our separate ways.”

Dean doesn’t look convinced, and Sam can’t blame him; he is pretty sure they all radiate equal amounts of suspicion. But they are short on options and painfully aware of it.

Cas speaks first. “We should all agree on it,” he says diplomatically. “If we don’t, if we think it’s too risky, we can try to exhaust other options.” He takes a searching look at Lucifer. “I agree to it. Dean?”

Dean looks disgruntled, but eventually says, “I’ll agree if Sam does.”

And that is how this world-altering decision is left to him, the impossible decision of either keeping the Devil locked up and the world safe from him and possibly dooming said world to Amara’s wrath, or letting out the angel who was once dead-set on ending the world and beat Dean down with Sam’s hands, and by doing so, possibly gaining a chance to save everyone from this mess they’ve created.

Sam has long since abandoned self-preservation and risk-aversion in favor of helping others, so the choice is clear, but that doesn’t make it any easier.

“Okay, let’s do it,” Sam says, and the decision feels like a stone in his chest.

Rowena begins preparing the required spell to get Lucifer out and Crowley fetches ingredients, while Lucifer takes this as his cue to move on.

“Now the only question remains: who am I going to wear?” he says. “I mean, I’m fine inhabiting temporary vessels if I must. It’s inconvenient, but doable.”

Cas shakes his head at that, and says, “That’s not a great idea. Those are innocent people you’d be killing, not right away but still, in rapid succession.”

“Oh, right, you and your…” Lucifer trails off and twirls his hand like he finds the intrinsic value of human life something barely even worth noting. It doesn’t surprise Sam, but Lucifer does reel it in a bit, conceding, “Fine. Then what would you suggest?”

Rowena chimes in with, “There is spell work I could look into, spells to fortify whichever vessel you should choose, maybe even a dead one if you’d like, my Lord.”

Sam rolls his eyes. Of course Rowena would my Lord the Devil. She looks positively smitten, while Crowley just glares at Lucifer silently, placing the bones he’s fetched into the pile of ingredients.

“A dead one? How does that work?” Dean asks.

“Magic tends to have ways around these things, should one know to look for them, and possess the skills to do so,” Rowena says, before frowning. “But, unfortunately, that may take a while, and I can’t promise you anything right away.”

Dean spreads his hands in defeat. “Great. So we’re back to square one.”

Cas has fallen quiet, but he speaks up now, asking, “What about me?”

The room—dungeon, limbo—goes silent as all eyes turn to Cas.

“What?” Dean exclaims then, and a renewed sense of dread washes over Sam as he thinks it over.

It makes a scary amount of sense.

Cas explains, “I mean, Jimmy is gone, which I’m quite certain was God’s doing, and I’m fine. I could theoretically serve as a vessel."

Lucifer rubs his chin in thought. “Hmm. An angel’s vessel, enhanced specifically for them. That could work. Good thinking, brother.”

“Cas, what—No!” Dean protests. “You can’t seriously be considering this!”

“Dean, what other choices do we have?” Cas retorts. “If we want Lucifer’s assistance, he needs a vessel. Do you want to see people get coerced to carry him only to be burned out in mere weeks, maybe months if we’ve lucky?”

“Weeks. Nick was the most durable vessel I could obtain, after my intended Sam of course,” Lucifer supplies, and though he doesn’t look smug while saying it, the choice of words makes Sam feel more than a bit sick to his stomach.

“See?” Cas says, pointing at Lucifer like that settles it, but from the look on Dean’s face he’d say the issue is far from handled.

He is right in that estimation.

“Cas, you still might not be able to take him on.”

“True, but I’m our best bet. And if I can’t handle it… I can always find another vessel. I’m not an archangel,” Cas tries to reason.

“And it might not work with your enhanced powers—you said it yourself!” Dean finally explodes, fear reeking out of him. “We’re not risking—“

“If I could interrupt this little domestic you’ve got going on and pitch in,” Lucifer cuts in, “I’ve got a suggestion: how about we share?”

“Share?” Sam, Dean and Cas all exclaim, almost in perfect unison.

“Yes. It’s hardly standard practice, but it should work. With Castiel so in tune with his vessel—quite like a human in that aspect—we should be able to switch who’s in charge at will. That would save you tearful goodbyes and I wouldn’t have act as messenger between him and you lot all the time.”

Dean crosses his arms. “And what if you decide to kill him while in his body? Decide it’s more convenient than knowing you’ll have to separate eventually. You could act like him and we’d only find out when it’s too late.”

“Dean, that won’t happen,” Cas states, and predictably, Dean scoffs.

“Oh, so you’re saying he couldn’t do that, huh?”

Cas only gives Dean an exasperated sigh.

Lucifer jumps in with, “No, you’re right, I could. But given the claim Castiel has on your soul it would be pretty obvious he’s gone, even to a human like you.” He sighs, concluding, “And if I killed Castiel you’d no doubt be motivated enough to find a way to stuff me back here again, since you have a track record with it, so no, I’m not planning to do any of that.”

Sam is still processing the way Lucifer managed to both insult and praise Dean in that one statement, when Dean is already asking, “Wh—A claim? What claim?”

“When I pulled you from Hell,” Cas explains, somewhat reluctantly, glaring at Lucifer for good measure. “It’s similar to bonds between angels and their vessels, if not quite as strong.”

“Oh.” Dean thinks for a moment. “The, uh… hand thingy?” he asks, and Cas nods. It tickles something in Sam’s memory, and he might be able to figure it out but doesn’t bother to; he is plenty busy actively trying not to think about the implications Cas’ words have on him and Lucifer.

“But how?” Dean presses, and Cas sighs, exasperated.

“Come here.“

“Cas—“

But Cas has already pressed his hand against Dean’s left shoulder, saying, “There,” and then they’re staring at each other intently and woah, yeah, this went there and fast. “Can you feel that?”

“Y-yeah. Yeah,” Dean chokes out, definitely feeling something.

“The scar has been healed, but the mark on your soul remains. There’s no one else who can replicate that. No magic, no grace, no matter how powerful, can make you feel the same, fool you that it’s me if it isn’t,” Cas says, before pleading, “Trust me, Dean. Please.”

“Okay,” Dean finally, reluctantly, and a little breathlessly, says. “Okay. We’re gonna talk about this later though, you hear me?“

“Of course, Dean,” Cas replies, and the two of them share another one of those long looks that always makes Sam feel like he is seeing something he’s not supposed to.

Lucifer seems to pick up on it, too. “Ugh, get a room,” he mutters under his breath, and no matter Sam's feelings about the Devil, he has to agree with the sentiment; he’s had a front-row seat to this particular show for years now.

“So we’re all agreed? This is our temporary solution?” Sam asks, only partly to confirm and mostly just to break off the staring contest.

Dean and Cas both nod, and Lucifer adds, “If we manage to beat Amara, it’s the first thing we’ll sort out.”

Yes, if. Even with Lucifer on their side Sam can’t help but worry about their odds, but it doesn’t do anything good to dwell on it right now. The only way is forward, no matter how it feels like trudging up old ground.

Soon Rowena is done preparing the spell and casts it, the stone floor starts to shake anew, and Sam watches as she undoes the work that took them the better part of a year and their friends’ lives to accomplish for a sliver of a chance at fixing this new mess they’ve made.

Such is the Winchester life, indeed.

Seeing Lucifer in Cas’ vessel is… weird to say the least.

The upside—probably the only one—to it is that their facial expressions and other key features are so different that even without any prior bonds Sam doesn’t think he or Dean would have much difficulty telling them apart. Where Cas’ range of expressions mostly consists of serious frowns, tired sighs, and bright smiles on occasion, Lucifer’s are all over the place, his movements more animated and his expressions spanning from stoic and pensive to sarcastic and wry and back again at a pace that would give the uninitiated a headache. Lucifer also uses the vessel’s vocal cords differently, producing a smoother and softer tone laced with a mightier-than-thou cadence typical to angels. Cas lost his years ago.

With Lucifer and Cas successfully mashed together, they make their way out of Hell save for Crowley and Rowena. They may be on their side, but the tenuous alliance is still far from shared strategy meetings. Rowena and Crowley seem to be willing to pitch in when needed, but the responsibility for finding a way to stop Amara falls on the Winchesters, as usual.

They get back to the bunker by car, Dean adamantly refusing to let Lucifer ride with them, even with Cas in charge. This isn’t an issue for Lucifer, who was in the cage when the big fall of angels happened and still has his wings, and even discounting his other powers it admittedly gives him more of an advantage against the Darkness over any other angel, Sam has to admit.

Back at the bunker, Sam focuses on considering the possibilities of that and what they know of Amara’s powers, instead of thinking about the fact that Lucifer is here with them, conversing with Cas somewhere while Dean and Sam settle in and take care of their human needs—chief among them, dinner.

Dean is gulfing down some leftover lasagna while Sam picks at his when Dean states the obvious. “He makes me nervous.”

“That makes two of us,” Sam replies, and it’s an understatement, but he’s holding on by a thread that hinges on no one paying attention to it, so that’s all he’ll say. No point in anything else. This decision wasn’t done without his input, so he has no right to whine about it. He will just have to deal.

Dean branches out to explain what happened while Sam was in limbo. Apparently, instead of sending Dean visions Amara came to him in person, talking about fate and this connection they supposedly have due to her being released from the Mark Dean last held. Amara seems to be targeting him because of that, and on some twisted level Sam is relieved it’s not him who’s haunted by the Big Bad for once.

“It’s really weird,” Dean concludes. “I tried to speak sense to her, but she just kept… coming onto me, I guess, saying we have this connection we can’t escape from.” Dean makes a puzzled face. “I don’t know what she’s talking about, cause I ain’t feeling that. Like, she feels familiar; she’s right there. But other than that…” He trails off with a shrug.

“Hmm,” Sam only replies. The whole thing is quite peculiar, sure, but Sam can pretty easily surmise at least part of the reason for that last thing, and it’s wearing a trench coat and currently occupying an archangel.

And speak of the Devil…

“Alright,” Lucifer appears in the doorway, clapping his hands together. “Let’s get to work.”

“Oh god,” Dean groans, seemingly struggling with seeing Cas’ body doing that even more than Sam is. Sam only sighs in capitulation.

The rest of the evening is spent in the war room, strategizing, if it can even be called that. Sam is shaken just from the fact that he’s sitting opposite Lucifer without bars between them, and Sam can see Dean is exhausted from the day he’s had, never mind how having Lucifer in the bunker must be messing with his sense of things. In the end, they decide their game-plan is to make one when they can get their heads together properly and call it a day.

Dean retreats straight to his room, looking ready to crash in. Sam stays behind, too keyed up to even think about resting.

Lucifer and Cas apparently change reins, because Cas approaches Sam in the library where he is going through lore. He does it carefully and even says, “It’s me, Sam,” as he reaches him. It’s a bit pointless, but Sam feels grateful for the effort, nonetheless.

“Hey,” Sam greets him back, and Cas sits down opposite him.

“How are you dealing with this?” Cas asks in that gravel of his, and Sam heaves a sigh.

In the years of knowing each other, Sam feels he and Cas have slowly progressed from allies to friends and finally, something like family, and where with Dean he usually keeps his more sordid feelings closer to his chest, Cas tends to inspire more casual honesty from him. “I’m… probably not sleeping that much tonight, or at all, but I’ll be fine.”

Cas is as used to ignoring the perpetual bags under Sam’s eyes as Dean is, bouts of anxiety and insomnia coming and going like a tide wave, and even without that Sam doesn’t think Cas would be surprised, given their circumstances. He just sighs, leaning his arms on the table.

“Sam, if it’s any consolation,” he says, “I don’t think Lucifer wants to hurt you. Had I sensed any animosity in him towards you, I wouldn’t have agreed to this in the first place. However, if I’m wrong, I promise you, Sam: I will not let him harm you. I know that you taking control of him was a once-in-a-millennia thing at best, but I’m certainly going to do whatever I can.“

Sam smiles at Cas’ sincerity and humbleness. “I don’t doubt that. And I’m sure you’d be able to take him on.”

“No, Sam,” Cas shakes his head, “You are among the only beings in the whole of creation who could stand against him and have a chance of taking him over.” Sam is busy trying to let that sink in when Cas continues, “But I’ll do my best. I know it’s… hardly enough to comfort you, and I’m sorry we’re in this situation in the first place.”

”I know, and it’s not your fault, not anyone’s, really,” Sam says. “Thanks, Cas.”

Cas takes that as his cue to leave, but before he can exit the room, Sam calls out, “And, Cas?”

“Yes?”

“Don’t sell yourself short.”

Cas smiles. “Good night.”

“Night.”

Sam stays in the library, keeps going through some of the lore books they haven’t covered earlier for mentions of the Darkness, reads until his vision gets blurry. He finally retreats to his room then, his body aching just from staying up this long, in addition to the weakness brought by the trials to close Hell he still feels intermittently. It’s been a couple of years since he was being torn apart from the inside out, but he is still on the mend from that. Since the damage reaches all the way to the fabric of his being, there is only so much even Cas can do. Sam has gotten used to it.

Despite his exhaustion, Sam doesn’t sleep that night. Lucifer is in the bunker, and Sam doesn’t know what he is doing, and even though his rational brain knows Lucifer would strategically gain little from hurting him, the fear and uncertainty persist and settle into a heavy ache inside him. He tries to distract himself with a random docuseries, gives up after retaining absolutely nothing, and then just stares at the wall as the hours go by slowly.

The irony of the situation, the real kicker, is that prior to this set of events, Sam had actually been doing better, compared to the utter mess the last few years have been. Not good, not ever good, especially with another apocalyptic danger looming over them, but managing at least, and even getting a few consecutive hours of proper sleep in occasionally. He might have been hanging by a thread, but it was a bit sturdier at least.

Now he feels completely unhinged again, pulled into another waking nightmare, and dreading everything that’s to come with it.

This whole operation has barely started, and he already wants to run away from it all.

Dean seems to be of the same mind, because in the morning he’s waiting for Sam with a case as an excuse to hightail it the fuck away for a day or two. He says they can scour the internet for references to the Darkness on the way, since the bunker’s resources have been all but exhausted.

Sam doesn’t need to be asked twice.

He doesn’t even have it in him to feel bad for leaving Cas with Lucifer. Dean obviously does, if the looks he keeps leveling Cas are anything to go by, and as Sam goes to get his things, he can hear the two having a conversation in hushed voices in Dean’s room. Dean’s seemingly come to terms with the vessel thing, letting Cas into his room with Lucifer tagging along in the back of his mind, so that’s good at least.

Sam keeps himself awake through the day with copious amounts of coffee and sheer determination. The case involves a very specific set of murders with a similar MO but different suspects, which indicates they may be dealing with a shapeshifter. The victims seem random at first, but as they eventually piece together from the statements from some locals and the police, it appears there is a common denominator: all three victims are once-convicted or alleged domestic abusers, two with sexual assault charges under their belts as well.

With that insight, they stop at a motel for the night to rack their brains, and Sam gets a blessed two hours in before waking up from a nightmare of Lucifer torturing Cas, but he’ll take what he can get at this point, not even really that disturbed afterwards.

They get the case finished up the next day when they manage to track down the killer. As suspected, she is a shapeshifter, a young and inexperienced one at that, and she had used her power to help some acquaintances of hers escape from their abusers where law enforcement had failed. Sam can’t in good conscience kill her for that, and even though Dean seems a bit more ambivalent, they agree to let her go on the condition she relocates and finds less homicidal ways to help people in the future. It’s not ideal, and she could fall on some other hunters’ radar if she ever displays her powers again, but she claims she won’t, and Sam believes her. Sam has made some difficult decisions in their line of work, some he still thinks about years and years later, but he doubts this will be one of them. Any case where they end up not killing anyone is a nice change of pace in his book.

When they get back that evening, Lucifer is pouring through some old books he says he picked up from Syria and Egypt at Rowena’s suggestion, and the bunker is still standing. Dean visibly relaxes a bit after that, no longer startling every time Lucifer enters the room or keeping him in his eyesight constantly.

Sam can’t really say the same.

It is harrowing, not feeling safe in this place that has become their home. He feels the safest in his room but that’s not much of an improvement, knowing Lucifer has no real reason to enter it but still knowing he could if he wanted to.

Sam spends the better part of that night looking through the books they have on sigils and the Enochian language, trying to find anything to help keep the Devil out of his space properly. While his angelic vocabulary and understanding of sigil formation have gotten better with time, they’re still far from perfect, and there’s so much nuance and missing information in the lore that makes it even more difficult. In the end, he’s pretty sure none of the sigils he finds are exactly what he needs, but he still spends hours carefully painting some on the walls already adorned with generic protective sigils, just to have something to do. It’s either that or succumbing to the fear and panic that have been building inside him ever since he realized he’d have to see Lucifer again.

Sam keeps painting sigils, using blood-infused paint the Men of Letters invented and had left lying around for them to find, until the walls are nearly covered, and then he thinks he better stop before he accidentally locks himself out of his room. After that, he’s still got some energy left, so he catches up on some news stories before his body finally shuts down.

He sleeps in tiny increments and wakes up gasping in terror several times in succession, but he wasn’t exactly Sleeping Beauty before this, so he thinks it’s better than nothing. He will make it through this and manage.

He has to.