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oOo

"Mouth so full of lies, tend to black your eyes"

- The Day That Never Comes, Metallica

oOo

"Dean!" The booming yell had the oldest Winchester surging to his feet, chair scraping across the hardwood floor of the library. Cas was hot on his heels as he rushed down the corridor again, the lights flashing like Morse code as he ran. He heard the panic in Sam's tone, the frantic banging of a fist against the wooden door.

"Sam!" he shouted back, twisting the handle. Nothing happened. He rattled it uselessly, the door refusing to budge. Turning sideways, Dean rammed himself into it, shouldering it violently. It barely shook. Sam's banging stopped.

oOo

"Sam!" Dean's reply was muffled on the other side of the door which Sam clawed at desperately until he saw his breath escaping in plumes as the temperature plummeted. The hairs on the nape of his neck were stood rigid, a tremble sliding smoothly down his spine, pooling fear into his gut.

Don't turn around.

It was ridiculous; he was a Winchester. He knew everything that hid under the bed, went bump in the night and lurked in the closet. And yet, the same intuition, the same knowledge, told him what was behind him now, breath whispering against his neck.

"You're not making this any fun" a voice grumbled, confirming his fears. He could almost hear the mocking pout in the tone. The beating on the other side of the door continued; Dean and Castiel's shouts quieter than before. He flinched when a hand gripped his shoulder, not tightly, but the touch was still oppressive. Possessive. It stayed there, heavy, unmoving as he fought to control his breathing which was hitching in his throat.

He was whipped around, the hand's owner finally tired of waiting for him to quell his fears, to fight back. His back was pressed against the door, the faint vibration of Dean's attempts to break in rippling through.

"Is saying no to me again everything you dreamed it would be?" Lucifer whispered, bringing his face uncomfortably close to Sam's. He was back in his original vessel, Nick. The Winchester screwed his eyes shut, stretching himself up to avoid the unwanted proximity. "Was your reunion with Dean magical? Did you have a broment? I bet you had such a broment. I'm surprised you're not out there polishing each other's guns or whatever it is you two do for fun" Lucifer smirked, enjoying Sam's obvious revulsion at his intended innuendo. "But wait," the archangel gasped dramatically, eyes wide as he morphed into Vince Vincente, "you still haven't got past the fun dry-out period, have you? Tell me Sam," he leaned in conspiratorially, yanking the hunter down to his level and locking eyes with him. "Do you wish you'd said yes, yet?"

Sam turned hard, fever-reddened eyes on him but said nothing. What was there to say? He ached with an agony that couldn't be suppressed, his mind constantly playing tricks on him. He couldn't even be sure that Lucifer wasn't there. Logically, he knew the archangel wasn't, but logic didn't matter. So he kept to his stoic silence, afraid of the answer he would give. Lucifer's eyes narrowed.

With a bored flick of his wrist, he flung the hunter across the room. Sam landed heavily against his desk, gasping when he hit the corner, the sharp edge smacking into his ribs. His hand snaked around to protect his chest as he struggled to his knees, looking up through the locks of hair that fell forward over his eyes. A pair of tan heels approached him. Toni's body leaned over him, Lucifer's smile cruel.

"How about in this body? Wanna say yes now? She would've you know. Over and over and over," he goaded, arching himself suggestively. Disgusted, Sam looked away, feeling his heart ram itself against his chest as the sight of Toni brought forth a horde of memories he couldn't deal with. His voice caught in his throat, paralysed.

oOo

"Goddammit, Sam, open the damned door!" Dean roared, whacking his now bruised and aching shoulder into the door again.

"Move" Cas ordered, pulling the other man out of the way. He raised a hand, palm open, concentrating directly on the door. The wood screeched and groaned, shuddering on its hinges as the angel tried to manipulate it. He frowned, concentrating harder. The structure whined under the pressure he was exerting yet it refused to move. He dropped his hand, scowling darkly. "I don't know how-" he began, an almighty crash interrupting him as the door suddenly exploded outwards, wood splintering, Sam landing in the corridor or, more precisely, on Dean, knocking him to the floor.

Sam choked, completely winded this time, fighting to draw a breath into lungs that had locked. He watched, horrified as Lucifer stepped through the threshold, standing over him, flicking his long blonde hair back over his shoulder. A hand gripped his arm and he snapped his gaze to his right, horrified to see Lucifer again, this time as Nick, latching onto him. He yanked his arm away, shying to the left. He bumped into something else – another hand landing on his shoulder. Sam looked to the left, eyes widening when Vince grinned at him.

"What's the matter, Sam?" Vince asked him, voice soft, his grin vicious.

"Get off me!" Sam cried, snatching his arm away again.

Dean looked over Sam's head at Castiel, brows furrowed. He made to reach a hand out again, stopping before he touched him when Sam flinched at the suggested contact. Sam gasped, grasping his head, wincing as pain throbbed through his temple. The ground began to tremble, a hard rumble that tremored beneath their feet. Dean looked at Cas in alarm.

"Sam! Calm down; it's just us" Dean urged, hands fluttering uselessly, wanting to touch his brother, afraid of what would happen if he did. The rumbling increased, making the shades on the hall lights tinkle in their fittings. Blood dribbled from Sam's nose. A light bulb burst.

Without warning, Cas' hands shot forward, one yanking Sam's arm down, the other pressing two fingers to his forehead as the other lights blew, plunging them into semi-darkness. Sam's eyes rolled back into his head, Dean just managing to catch him as he slumped backwards, cradling him in his arms. The rumbling stopped.

Dean scowled at Cas.

"What did you expect, Dean?" Cas growled, standing up over them both, knowing exactly what angered him. "Couldn't you feel the power coming from him? Sam's condition is dangerous and unpredictable; we've never done this after he's consumed so much blood. Do you want him to destroy the whole bunker with us all in it? He's just proved he's capable."

Dean's jaw worked, the muscles twitching. "He wouldn't. You had no right."

"He could. At the moment, he doesn't know what he's doing and, deep down, you know that too. What is he going to have to do to make you see that?"

The oldest Winchester looked away, refusing to answer. Guilt wracked him. Sam trusted him and he wouldn't break that trust.

They would find another way.

oOo

Gatwick Airport, London

"Final boarding call for passengers of the British Airways flight number BA7983 to Kansas City."

The soft feminine voice echoed throughout the departure lounge which teemed with swarms of people as they rushed, ambled or procrastinated, most getting in the way of each other. Thomas cast a scrutinising gaze over them all; Toni had always hated the airport. Large crowds of hollering, whining civilians got on her nerves. Thomas couldn't blame her. Most of these people were sheep: bleating about nothing and blind to the things that really mattered. Regret tugged at him, making him wistful. Most of them should have been dead by now, slaughtered by Lucifer in his bid to purge the world.

"Thomas?" The voice was gentle, nudging him from his reverie. Anna looked back at him from across the boarding desk where a woman in a smart navy suit looked at him expectantly, her smile plastered in place.

"I do apologise" he murmured with a soft smile as he stepped forward, handing her his passport. "Lost in thoughts of a better time."

"Something I think we're all guilty of now and again" the attendant chuckled, scanning his boarding pass. "Is your trip business or pleasure?"

"Strictly business, I'm afraid. I need to collect something that was taken. Put the opposition back in their place as it were."

"Ah. Well, I hope you're successful" she replied, handing him back his passport and boarding pass.

"Oh, I intend to be. Thank you" he nodded, giving her a polite smile as he walked through, joining Anna as they entered the tunnel leading to the aircraft.

It felt good to have a clear objective again.

oOo

Lebanon, Kansas

Castiel had gone, claiming an errand to do with the search for Lucifer, but Dean knew better. After they'd hauled Sam back into bed, removing the remnants of the door that was hanging off, their words had been heated, raised voices moving away from Sam. They had come to an impasse, both too stubborn to back down. Dean knew what was best for his brother and that was the end of it.

He sat stretched out on his bed, door wide open, the CD player next to his bed playing his favourite Metallica compilation. The Day That Never Comes rose up through the speakers, the soft guitar solo at the beginning drifting lightly through the room. Normally he'd play it loud – it wasn't the type of music that should be listened to quietly – but everything felt like it had to be quiet. He was constantly on edge, waiting for Sam to need him. He'd already been in to check on him four times in the last hour. Obsessive didn't quite cover it. Each time he'd gone in, Sam had been sleeping soundly for the first time since they'd got back. Begrudgingly, Dean was almost grateful to Cas for it. That still didn't mean taking away Sam's choices was right.

He sat there, stretched out, letting the music wash over him, granting him a few moments peace.

oOo

Consciousness returned slowly, the fog in his head slowly dissipating, lifting and clearing from the edges of his mind. Cracking his eyes open, Sam peered through the slits in his vision, relieved to see he was alone. Light pooled in through the open doorway – where the hell was the door? – spilling gently onto the floor. He blinked properly, raising a hand to rub the sleep from his eyes. Stretching out, he winced, feeling a sharp pain in his side. Probing lightly with his fingers, he winced at the tenderness around his ribs which sported an ugly purple bruise when he lifted his shirt to look. He couldn't remember doing it. Taking stock of the feeling in the rest of his body, he felt nothing else untoward. In fact, he felt good. Refreshed. The heat that had been sitting behind his eyes had gone, the throbbing headache too.

Flinging back the sheets, Sam sat up, wobbling slightly when he stood. Okay, he wasn't perfect, but he felt a hell of a lot better than he had done. The stone floor was cold beneath his feet as he padded towards the door, running a hand back through fluffy hair. His door was lying propped up against the wall in the partial darkness. Sam frowned; he didn't remember the lights breaking. Yawning widely, he rubbed the back of his neck, walking down the hall, heading for the kitchen. Dean's door was open, Metallica playing quietly, and he gave a sleepy wave without looking in.

Stepping down the stairs into the kitchen, the hunter looked around, crinkling his nose in disgust at the heaped pile of dishes. He couldn't remember when he'd last cleared anything away in the kitchen; it'd obviously been a while. Shuffling to the fridge, he tugged it open, disgruntled by the nearly empty shelves.

"How you feelin' Sammy?" Dean's voice wafted over his shoulder as he stared at the fridge, willing something to appear.

"We really need to do a food run" he grumbled, snatching the packet of coffee and closing the door.

"Yeah, well, we've been a bit preoccupied" Dean replied, leaning casually against the wall by the coffee pot. Sam nodded, a jolt shocking through him when he made eye contact with his brother. He got a hold of himself, grabbing the coffee pot and heading to the tap.

"Grab some clean mugs – if you can find any" he said, voice coming out high, strangled as he made a show of running the tap. Dean nodded, black eyes flashing, clearly unaware that Sam had noticed as he stalked past. Sam waited. Glancing over his shoulder, he saw his brother's back was turned as he reached into one of the cupboards for mugs. Moving on instinct, Sam launched himself, smashing the coffee pot across the back of Dean's head. The glass shattered as the hunter crumpled to the floor. Sam cursed, dropping the handle of the pot, the plastic clanking loudly on the stone floor. He turned and ran, hurrying to their equipment room. He wouldn't have long.

Grabbing a pair of handcuffs, he raced back to the kitchen, relieved to see Dean lying where he'd left him. Approaching cautiously, Sam nudged him with a foot.

Nothing.

He bent down, grabbing Dean's left wrist quickly, snapping one cuff around it as he grabbed the other, securing the second cuff to his other wrist with the metal pole of the kitchen counter between his arms. Sam scrambled away, sitting on the floor staring at his brother's unconscious form. They'd cured him! Dean couldn't be a demon again; he couldn't – wouldn't – believe it. If he hadn't stared into the endless black encasing Dean's usually warm green eyes, he wouldn't have done.

How could he put Dean through this all again?

He had no choice though; if Dean was a demon, he had to be cured. Sam couldn't lose his brother again. Not when he could change it.

Getting to his feet, he staggered out into the hall, heading for his files in the main library. Nausea filled him, roiling in his empty stomach. He'd give anything not to have to do this. How did it even happen? Hadn't the cure worked properly the first time? Sam yanked on the second drawer down on the filing cabinet open, flicking through the files quickly, his eyes scanning the labels. He stopped, half pulling one out, checking it. Satisfied he had the right one, he hurried through the other side of the bunker, heading for their dungeon (as Kevin had so aptly put it). It had been sealed for a while; they had had no need of it. The hunter pulled on the shelves, opening the space up and switching on the lights. The chair at the centre still sat in the middle of a Devil's Trap, demon chains left around its base. He needed to get Dean in here before he could get the purified blood. He really needed Cas but the angel wasn't well – he needed to concentrate on getting his Grace back. Sam could handle this. Putting the file on the table, he picked up the warded handcuffs and left.

Edging back along the hall, he concentrated his hearing. Metallica's Enter Sandman floated to him quietly, the CD player still going in Dean's room. Everything else was silent save for the sound of his own breathing. Rounding the corner, he stepped into the kitchen.

And stopped.

The room was empty – the silver handcuffs lying open on the floor. His heart skipped a beat.

"Sammy…" the voice crooned, echoing throughout the bunker. Sam jumped, slipping into the kitchen and pressing himself up against the wall, making himself as invisible as he could. He held his breath, swallowing the panic that was rising in his throat. "C'mon little brother, let's play a game" Dean's voice called, gruff and mocking. A scraping sound, like metal on plaster screeched through the hall, sending Sam's heart thumping. He knew that sound.

A hammer.

He couldn't do this. Not again. He looked around frantically, not even sure what he was looking for. His fingers clenched and he looked down, realising that he only had the demon cuffs with him; he needed a weapon. Where the hell was the Kurdish blade? Sam nearly groaned aloud when he realised. The Impala. They'd been on a hunt. Stuffing the cuffs in his back pocket, he listened again, trying to decide which direction the scraping noise was coming from.

"C'mon, Sammy; it's no fun when you don't play along. I've even got a new proposition for you."

Darting out from the kitchen, Sam dashed out and left, stopping and sheltering in his brother's room.

"What could you possibly want to offer me?" he shouted back, letting his voice carry before running again. He made it into the library before Dean's voice floated back.

"Don't be coy, Sammy; I know what you want."

"I want my brother back" he retorted as he studied the library, calculating how long it would take for him to get across the space. Dean's dark chuckle was full of malice.

"When will you get tired of lyin' to yourself? That's not want you really want. You want what's in me. You want blood." Sam moved, feet slapping against the floor as he sprinted towards the door to the garage. A hand grabbed his upper arm, yanking him to a halt, his brother leaning in close, whispering in his ear.

"I want to give it to you."

oOo

Dean groaned, wincing when he felt cold seeping into his cheek. His head throbbed painfully, a damp warmth spreading just behind his right ear. He moved to touch it and found his hands didn't cooperate. Opening his eyes, the hunter lifted his head.

"Son of a bitch" he growled, staring at his own cuffed hands wrapped around a metal pole. Wincing, he pulled himself up, glass tinkling around him as he sat up. The smashed coffee pot pieces were strewn across the floor. He'd been glad to see Sam up and about off his own accord – relieved even. Now he cursed himself. Dean couldn't understand what would force Sam to attack, but, whatever it was, it wouldn't be good. Pulling himself up, using the pole for support, the cuff clinked against it. Reaching awkwardly into his jeans pocket, he pulled out his set of lock picks. Sam must've been out of it if he hadn't even confiscated them from him. He set to work on the locks.

oOo

Sam forcefully jerked his elbow up and backwards, catching the demon straight in the nose, snapping his head backwards. Blood spurted as Demon Dean let go of him, hands cupping his face. Sam shot forward, bolting through the door and up the steps into the garage. The lights flickered on overhead, revealing the bunker's collection of classic cars. The Impala sat shining in the middle, perfectly cleaned and gleaming.

"Sammy?" he ignored the call again, rushing to the trunk.

oOo

"Sammy?" Dean shouted, running through the bunker, searching desperately. He had no idea how long he'd been unconscious, no idea where his delusional brother would go. The library was empty, everything where it should be except for one of the filing cabinets which had its second drawer open. The hunter slowed, caution filling him. He listened, hearing nothing. Proceeding through the library, he peered around, alarming filling him when he saw the door to the garage open. He ran through, taking the steps two at a time.

oOo

Sam managed to extract the knife just as the demon descended on him. He slashed at his brother warningly. Demon Dean grinned.

"You don't really wanna use that on me, Sammy" he laughed, arrogance pouring from him in waves.

"No, I don't," Sam replied, keeping the knife raised, the Impala at his back, eyes fixed on the imposter. He absorbed Demon Dean's air of confidence, noting the long, clawed hammer hanging from his left hand, seemingly loosely but he could see the tautness in his arm. "But you're not well, Dean. You don't want this. Let me help you."

oOo

"How could you help me?" Dean asked, confusion colouring his voice, furrowing his brow. Sam swayed lightly on his feet, a sheen of sweat coating his skin. His eyes were dark and bloodshot, unfocused. The hunter had no idea what he'd walked in on. Sam kept the knife raised as he reached into his back pocket with his other hand, pulling out the warded cuffs which they kept in the dungeon. He held them up. Dean stared at them, incredulous. "You expect me to put them on?"

oOo

"I want to help you, Dean and I know, deep down, you want me to. Please. Don't make this harder than it has to be" Sam implored, shifting uneasily. He wished Castiel was here. Staring down Demon Dean was like facing off against a viper; one wrong move and he was dead. The demon sighed dramatically, rolling his eyes. He held out a hand. Sam hesitated.

"You win, Sammy" he sighed, taking a small step forward. Sam reached out, knife still raised, the cuff open as he aimed for his brother's wrist.

oOo

Dean tensed, regret filling him before he'd even moved. Sam edged forward, cuff and weapon raised. Dean put out his hand, letting the metal come within centimetres of his wrist before he twisted, snatching hold of the cuffs and turning it back on his brother, snapping it around his arm.

"No!" Sam gasped, slashing at him with the knife, narrowly missing Dean's cheek as he dodged. He grabbed Sam's other wrist, slamming it against the side of the Impala, forcing him to drop the weapon. Despite his fever, Sam fought viciously as Dean grappled with him, trying to snare his other wrist with the cuff.

"Dammit, Sam, stop!" he shouted, panic in his own voice as Sam tried to wrench away, fighting and kicking. Dean twisted to the side, kneeing the back of Sam's legs, dropping him to the ground. The older Winchester looped his arm around Sam's neck, squeezing his carotid arteries. Sam's hands flailed, batting at his arm as he held on. "I'm sorry," Dean choked, repeating it over and over softly in his brother's ear, Sam's hair tickling his cheek. He felt his brother's grasp on his arm slacken. Moments later, Sam's whole body slumped. Dean let go, his arm dropping to around Sam's chest, pulling him to him as guilt ate gnawed at his gut.

Cas had been right.

oOo

Hauling his gigantic brother back through the bunker was no easy task, but he managed, fuming with himself the whole time. He just hoped Sam would forgive him when the time came. Dean doubted that Sam would remember what he'd done, but when the detox finished, he'd be pissed that he was restrained. That was a best-case scenario. The likelihood that he woke up and panicked…

Dean couldn't think about it.

He finished wrapping a soft cloth around Sam's wrist protectively before closing the warded cuff around it. Both chains were long and bolted to the floor, giving Sam full flexibility in the chair and room to stand and manoeuvre within the Devil's Trap that was marked on the floor. There was no reason to restrain him further. Dean slid down against the wall, elbows resting on his raised knees as he ran his hands through his hair. Pressing play on the CD player he'd collected earlier, he turned it down low, letting it play just loud enough to dispel the oppressive silence.

Then he waited.

oOo

"Rise and shine, Sammy!"

Sam flinched, jerking bodily awake, alert in an instant. His eyes snapped down when his arms didn't move, horrified to see the ropes wrapped over his wrists on either side securing him to the chair. Panic clawed at him, scrambling up through his throat as a tiny whimper. He tugged desperately, muscles taut in his arms but the rope didn't budge. When he tried to lean forward, something choked him. Looking over his shoulder, he saw a thick chain reaching from the floor all the way up to his neck. An image of Crowley, sat in a church, chained and collared surged to the front of his mind. Oh god.

Hey I'm your life, I'm the one who takes you there.

The music penetrated his senses softly as Dean crouched down in front of him, black eyes grinning up at him.

"No" Sam moaned, squirming miserably. This couldn't be happening. Where was Cas?

"You didn't give me any choice, Sammy" the demon sighed, rising to his full height in front of his brother. "But don't worry – I'm gonna cure you."

"I don't- you can't do this!" Sam groaned, his eyes wide, panicked, his own pupils huge. He watched, horrified, as Demon Dean pulled a syringe off the small table, making a show of balling his own fist and sticking it into his arm. Sam's eyebrows knitted together in confusion as he pulled the plunger back, filling the syringe with a swirling dark liquid, all the while keeping his eyes fixed on Sam, a grin spread wide across his features. He extracted it and moved towards his squirming brother. He grabbed Sam's face, digging his fingers in painfully to Sam's cheeks.

They'll betray. I'm you're only true friend now.

"I know it doesn't seem like it but I know what's best for you, Sammy," the demon insisted, holding the syringe close to his face, enjoying Sam's wide, frightened gaze fixate on it.

"You can't…please! Don't do this, Dean, don't. I know you're in there somewhere. Please" Sam begged, hot tears welling at the corners of his eyes.

"It's okay Sammy; I'll take care of you. I've got everythin' you need. Soon we'll be together again – properly – as brothers." Demon Dean whispered, releasing his hold.

"No! My brother would never do this to me. Stop" Sam whimpered, tugging futilely against the ropes.

oOo

Dean sat, shocked, unable to move. He couldn't. The guilt swallowed him at Sam's words. He knew Sam was delusional, but still his words hurt. My brother would never do this to me. This wasn't what Dean wanted. Not at all. But what choice did he have? He couldn't control Sam, couldn't stop him from attacking him – or worse – leaving the bunker. The way he refused to even look at Dean, who hadn't braved going near him, made his heart ache. Sam was completely tense, his hands gripping the armrests until his knuckles were white and the muscles stood out beneath his skin. His back was rigid, neck straining. Dean knew this stage; if it wasn't for the warded chains, the blood would probably have started flinging him across the room again. Instead it seemed to be internalising, making Sam's body painfully tense as it fought the effects.

"It'll be okay, Sammy. Trust me" he mumbled, his words hollow, unconvincing even to himself.

oOo

"Trust me" Demon Dean smiled, bending down and turning the dial up on the CD player in the corner, Metallica blaring louder and louder until it was deafening. Sam winced as the music thrummed in his ears, booming through him. The speakers shouldn't get that loud, a part of him knew that, but still the demon kept turning the dial. The chair, the floor, began to vibrate, as the bass tremored through.

I'M YOUR DREAM. I'M YOUR EYES. I'M YOUR PAIN.

His brother sauntered back over to him, grabbing his arm just above the ropes, holding him still.

"No! Don't!" Sam shouted, but he couldn't even hear himself over the music that sent painful tremors throughout his body. He writhed, struggling desperately as the needle approached his skin. He didn't want this! His brother as a demon and him on demon blood? Bile rose in his throat at the throat. He couldn't even comprehend the damage they would do together. It couldn't happen. He couldn't let it! He shouted and yelled desperately, the sound lost even in his own ears as the needle slid in.

He couldn't stop it.

The plunger was pressed, the demon blood slithering smoothly into his veins. Everything burst into flame, his insides reacting immediately, almost enjoying it, letting it flush through him. His heart pounded, sending it reeling around his whole body as the bass of the music set every nerve on fire. He'd been clean for so long. Tears slipped from the corners of his eyes as he screamed in agony.

This was it.

I'M INSIDE: OPEN YOUR EYES. I'M YOU.

oOo

I hope that didn't get too confusing – trying to write two Deans is hard!

Please review!