Because Dean had been spending his days with Cas, Sam didn't actually worry when he came back to their room in Zachariah Kline's house one evening to find that Dean wasn't there. He called his brother, and when there was no immediate answer, left a message. Hey. Tell me when you'll get back. If they were in the middle of a case he'd be worried at the fact that Dean didn't answer.

Here, now, he didn't worry. Not at first.

Half an hour later he was worried. He didn't bother to ask Zachariah for use of his truck, but hotwired it and cranked it into full gear. He went straight to the Kline house. His phone was open beside him on the seat, for when Dean rang back.

Dean didn't ring back.

The Kline house looked as it always did; ramshackle and empty. The Impala was parked on the drive. Sam cocked his gun and held it in front of him as he stepped up to the porch and creaked the front door open. Half of him was ready to be made a fool of. Was praying that he would be. It ran in an endless loop in his head: please God. Let Dean be okay. Let him be in the middle of things with Cas. Let his phone have fallen under the bed and he didn't notice. But even as he prayed, he kept his eyes fixed on the shadows inside the house.

Cas was not there. Dean wasn't, either. Not on the first floor. Not in the kitchen. Sam looked up at the empty stairwell, and felt the grip of his gun grow slippery with sweat. He walked up, one foot in front of the other, against the banister so the steps didn't creak. He didn't think to see Dean in any of them, but he checked the rooms along the hall. The old man was still there; he was holding a book, and the light from his round spectacles—glanced around the shadowed hall. The last door, then.

Sam wasn't sure why his heart was in his throat. He wasn't sure why he thought he'd find something behind it.

He turned the knob; toed the door open. And he saw—

—"No," Sam said, squinting into the emptiness as though into a gale. The empty room. Bare, and blank. "Where's Dean?" he said. "Where the hell is my brother?"

There was nowhere else to go but in. So he did.

/

It would be unfair to say that Sam saw the creature when he stepped inside. But he sensed it; he became aware, and was firing off two shots before he'd thought better of it. They embedded themselves into the wall opposite, and a crack was forming in the room.

A movement. Sam swung around, firing again. And again.

Had he run out of bullets already? How many times had he fired? And how had he missed the creature, when it was in all of the room already? Pressed up against the walls? With a slick, moving sort of sense to its edges where it—it was moving in on him, like it realized the bullets were gone. The gun spun out of his hand onto the floor. It was in the corner. Far. Too far to lunge. And useless besides. It was all around him, and he couldn't move with the way it held him in its grip. Too many hands? But were they even hands. He felt almost as though he were inside. A flower pressed between the pages of a book. It was becoming hard to see even the disgusting walls. Something was blocking the way. And he couldn't move. A ringing in his ears, so he couldn't tell if he was screaming—but he didn't think he was. Something was blocking the sound. Something that spoke.

You will die, it said. It wasn't a threat, just a statement of fact. Sam knew it was true, and felt tears rolling down his face. His chest heaved with the struggle to draw in air. To keep moving, to keep—being. I can offer you another option.

What option? Sam thought. Fatalistically. The monster had found him; as it always had. There was not even surprise, anymore.

The chance to see your brother again. And that meant—what? Dean wasn't dead? Who knew what it meant. But still.

In exchange for what? He knew what he was expecting. What they always asked for. 'Your soul.' But it didn't. It didn't.

I need you to let me in. I need you to say yes. It was not really better. Still, Sam wasn't ready yet to die.

Yes, he thought. Yes, yes, yes. And even though he didn't know what he was agreeing to, part of him knew this would be the end, as surely as if his heart had been ripped from his chest.

It. Came. In.

The whole expanse of it. The soft, slippery long limbs. The tight coiled heat. The soft mouths and the rolling eyeballs, one after another like a row of forks on a wire. The feet with their ankles turned up and the other parts; the more and more and more that had filled the empty room. Sam was sagging to his knees held up only by the force in his throat and snot was spilling onto his cheeks and he couldn't breathe. But the whole room wasn't finished. The thing in the room wasn't finished. It had been diffuse, and now, as it pressed inside, it became dense, as it crushed close enough in all the open spaces to fill them. Sam had never realized he was made of so much open space. There was space in his lungs that became filled with seaweed; there was space in his veins that became filled with intestines; there was space in his gut that became filled with stones, and his belly that became filled with meat, and the soil that filled his throat with slime behind his eyes, and inside his eyes with other eyes, one on top of the other like stacked coins. At last it had gotten all inside, and sighed then, as though in satisfaction. Sam had never realized how much he was made of empty space until all of a sudden he wasn't, and he wondered how he hadn't drifted apart into his constituent atoms before this. Now, when the humming shiver of energy kept him from drifting apart. Filling his fingers and his fingernails. It was no surprise that the thing was what stood up, and moved its head and cracked its knuckles; for the thing took up more space than Sam, and Sam was really just a space for it to get inside, a soft warm open little thing for it to get inside. And in return Sam just had to not worry, but Sam was still worrying, Sam was screaming, only he couldn't scream because his throat wasn't his own anymore.

What? it thought.

Sam didn't think he'd been screaming words, or any actual concept besides a horror he couldn't place, but it turned out he had. It turned out there was something playing on loop inside their heads and it was this: where's Dean where's Dean where's Dean where's Dean where's Dean

Okay, already. Give me a moment. The thing looked around as though trying to get its bearings. For the first time Sam wondered if it was as put off by the new situation as Sam, because there was something hesitant in the way it moved. Something not-quite. Then it took a breath it didn't need in Sam's lungs, and it snapped its fingers, and—

"Shh, don't wake him," Castiel said, looking down at Dean, asleep beneath a tree. He turned around, then, and squinted at Sam in reproach. "What are you doing with him?"

"Nothing he didn't ask for," it said, almost defensive. "You could say the same of yours."

And at that, Castiel did seem cowed. He pressed the nails of his fingers very hard in his hands, and looked down. At an awkward angle, not as though he was looking at something but as though he was trying to get away from himself. He breathed a constant, steady hiss of breath from his mouth like the teakettle; but very quiet. He seemed to want not to move. "I only did what I had to," Castiel said, much later; but the fact that it had taken him almost an hour to answer didn't seem to worry the thing. "It's what heaven requires." He sounded as though someone had taken sandpaper to his already abused throat.

And. That…

Heaven? Sam thought.

Castiel looked over at him as though he'd heard Sam speaking. "I suppose I should explain," he said at last, uncertainly. The thing didn't reply, so Castiel continued.

"Perhaps you will understand, Sam. I know you're a man of faith, unlike your brother. I know you've always believed in angels."

/

"Six thousand years ago," Castiel explained, "angels walked the earth as they would. But then a prophet closed the gates to heaven. Since then, we've been trapped there. As the Necronomicon says: The Old Ones were, the Old Ones are, and the Old Ones shall be. Not in the spaces we know, but between them." Castiel shrugged, then; as though he felt a motion was appropriate and didn't know what else to do.

You're the Old Ones? Angels? Sam thought; aghast, yet not unbelieving.

"Some of them," the thing that wasn't Sam replied.

"Yes," Castiel said, pensively. "Some of them. Others are much older; much more removed from the aspect of your four-dimensional world." He continued: "We've been trying to get out ever since."

Why now, Sam thought.

"Politics," the thing replied. "They needed an archangel's help to make a creature able to open the gates. A full-powered archangel, not whatever they'd be able to squeeze through the cracks as an abomination."

Castiel stared into the distance. Sam was aware, suddenly, that when the thing said abomination it meant, chiefly, Castiel; and there was something in Castiel's non-reaction that told him this wasn't the first time Castiel had heard it.

"We had to get in contact with hell," Castiel said at last, bleakly. "At least that is how Michael explained it."

"He was right," the thing said. "You'd never make it without me."

Without— Sam echoed, wondering; hell? What now? Could it get any worse? Somehow, he was sure that it could.

"Lucifer," Castiel said, nodding to the thing that wasn't Sam.

If Sam could have done anything then, he would have flinched.

"I had to ready a vessel," Lucifer said off-handedly. "You know yellow-eyes had plans for you, right? Ever wondered what those were?"

No, Sam thought. No, no.

Sorry, kid. This was planned from the beginning. You were never getting out of this town; not whole, anyway. The thing—it—Lucifer sounded almost sorry.

"Now all that's left is the ritual," Castiel said; as though that came close to explaining anything. "And then the gates will be opened."

"All the gates," Lucifer said grimly. "Not just heaven and hell, but purgatory too, and even the nameless place behind the nameless key."

"You fought it off before," Castiel said.

"With God's help," Lucifer said. "Where is he now?"

Castiel couldn't answer.

.

.

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