Set: Season 8 but AU
There's a good reason Sam didn't look for Dean or Kevin: Sam has post traumatic amnesia and doesn't remember the last seven or eight years, he thinks it's 2005/06. He's spent the year trying to piece together what happened to all the people he remembers still being alive: His Dad, Jess, Bobby, Dean, Pastor Jim, etc and what happened during his 'missing years'. By the time Dean returns, Sam knows what happened to him during his missing years by reading his hunting journals, but the memories and details are missing.
Dean's reaction and how he finds out is up to you.
Dean noticed it the second he put his arms around Sam. Maybe even before that. Something about his reaction was just off.
Since their bizarre lives never let them rest in peace, they’d been reunited after a summer of being dead or in another dimension several times, but none of those reunions had felt this wrong. Even back when Sam had lost his soul, he’d at least tried to mimic enthusiasm. What he saw on Sam’s face now was somewhere in between confusion and terror.
“You okay, Sammy?” he asked.
Sam nodded, and a few strands of his hair fell across his eyes. “I’m just — I’m surprised your back. I— I mean I’m glad. Where were you?”
“Yeah.” Sam had been there when they’d stabbed Dick and he’d exploded, or imploded or whatever the heck it was that had sucked him and Cas into Monsterland. He’d seen it happen. How could he not have known.
“How’d you get back?”
Dean wasn’t quite ready to talk about that just yet. “Found a trap door. Got tired of waiting for you to bust me out.”
“Oh…” Sam looked down at the floor awkwardly. “I was supposed to bust you out?”
Dean stared at him. “That’s what you do, isn’t it? That’s what we do. One of us dies, or goes to Hell or wherever, the other one finds a way to get him back. That’s what we’ve always done.”
Sam scrunched up his brow. “I thought an angel got you out of Hell?”
An angel? “Yeah, an angel did. Cas did.”
For nearly thirty seconds, Dean waited — expecting Sam to ask if Cas made it back too, but he didn’t. Sam just stood there, like he was trying to think of something to say.
“You hungry?” Sam asked, looking hopeful.
Dean nodded. He was starting to wonder if he’d accidentally landed in bizarro-world, instead of the normal one. Something was horribly wrong, but his gut told him he had to handle things carefully. Sam was acting almost skittish. Plus, he should be starving by all rights, anyway. He hadn’t eaten decent food in months.
“What was Purgatory like?” Sam asked after they placed their order.
“It was…violent.” Dean shrugged. “Not as bad as Hell, but then, nothing is, right?” He gave Sam a knowing look, but got an eerily blank expression in return. Sam might have shut out Hell as best as he could, but there’s no way he could have blocked it that completely. That just wasn’t possible. “What I still don’t get is what happened to all the fangs and wolves and big-mouths I killed down there. I mean, I never saw the same one twice, I guess, but still— if that’s where monsters go when they die…” Dean stopped talking when the waitress came by with their food.
Sam smiled politely at the waitress as she left and started eating one of the fries on his plate.
Dean had forgotten how long it had been since he’s eaten until he smelled the meat and cheese. Suddenly he was ravenous, and wolfed down half of his burger before he noticed something was wrong.
"Okay that does it," Dean said.
Sam looked nervous, and glanced down at Dean's plate. "Burger not good?"
"No, it's great. In fact, it's awesome." He pointed at Sam's plate, which held an identical cheeseburger. "But since when do we have the same taste in food?"
Sam shrugged, "I felt like a burger."
"You? Mr. Rabbit Food?" Dean took another bite of his burger, savoring the taste, and watched Sam eating his. Something was definitely different.
"What happened while I was gone?" Dean asked when they got back to Rufus' cabin. "You seem weird. Like— even for you, weird."
Sam swallowed. He looked like he was about to say something, and changed his mind. Then he looked at Dean steadily and said, "I forgot."
"That much, huh? You can just give me the highlight-reel man, that's okay."
"No, I mean, I forgot. Everything." Sam walked over to the couch and sat down.
"What do you mean, everything?" Dean set the six pack of beer on the coffee table, and propped his feet up.
"After you disappeared...I made it back here somehow. Back to this cabin. But I couldn't remember how I'd gotten here, or what I'd been doing. The last thing I remembered was walking home from Sociology." He looked up at Dean. "Back at Stanford."
Goosebumps prickled up the back of Dean's neck. "So you just...what — forgot the last eight years?"
Sam swallowed and nodded. He looked almost ashamed. "I looked in the mirror, and barely recognized myself. I kept wondering where I was, where Jess was. I tried calling your number, and Dad’s—“
"My number from 2005?"
"All the numbers I knew were disconnected. All of them." Sam shook his head. "I felt like I was going crazy. And then I found these." Sam nodded to the small table on his right, where he'd stacked up their Dad's journal and all three of Bobby's.
"You read 'em?" Dean asked.
"Twice, all the way through." Sam's mouth twitched. "Bobby's dead too, isn't he?"
Dean stared at his brother.
"And Dad, and Jess,” Sam said. He knew the answer, but it was obvious it wasn’t easy for him to say, let alone accept. “Jess — she died the way Mom did.”
“Yeah.” Dean turned to look at Sam, trying to think of what he could say, or what he should say. Back when Sam had gotten his soul back, he’d had amnesia of sorts too, and when his memories came back, they almost destroyed him. What would happen when the dam broke this time? “Sam, it’s—”
“She died because of me.” Sam reached for one of Bobby’s journals — the one at the very bottom of the stack, and flipped it open. “Everything those poor boys have gone through — all of it was because Sam was meant to be Lucifer’s vessel. And now he’s gonna say ‘yes,’ — let the Devil in, because he thinks he can actually beat him. I tried to talk him out of it at first, but I don’t know what other choice we have.” Sam turned the page and ran his finger down the center. “How come you’re here?”
“I told you, I found a way out,” Dean said, taken aback by the question.
“No, I mean…how come you’re here with me? How can you even stand to look at me, after the things I’ve done?” Sam tapped his finger against the journal page, once. "I cracked open Lucifer's cage. There were earthquakes that killed hundreds of thousands of people. 7.6 in Portland, 8.1 — all those people dead, because of me."
"Yeah and the rest of the planet is alive because of you! You let him out, but you locked him back up too. You spent a year and a half down there with him. 180 years Hell-time. It almost broke your brain." Dean paused, pinching the bridge of his nose, and looked back at Sam. "It did break you, for a while. You were seeing Lucifer everywhere, heard him in your head. You've suffered enough. We've suffered enough."
"I need to know what happened. I need to understand why — why I did all this."
"Because you thought you were doing the right thing. You always believed that."
"That's not enough. Dean, you have to fill me in. Tell me exactly what went down after Stanford. I deserve to know."
Dean's fist clenched. "You're not gonna let this go, are you?"
"How could I?"
"You have any idea what I would give some days to forget it all?"
Reaching for one of the beer bottles in front of him, Dean sighed. “October 2005, Dad disappeared. I came to get you at Stanford the day after Halloween...”