The three angels spread out to cover more ground, and searched for anything. A door, a window, any sign of life or existence they could find, anything that was different from just endless darkness.

Little did they know that they weren't the only ones doing research.

******

"Dean," Sam urged, nudging his brother. No response. "Dean," 

The eldest Winchester had fallen asleep in the bunker's library. Dozens of books littered the table before him, but the hunter was out cold. Sam sighed. It was no use trying to wake him, and Dean could probably use the sleep anyways.

It had been a couple weeks since Cas had died, and Sam wasn't even sure when the last time his brother slept was. 

Or the last time he showered.

Or ate.

Or had a normal conversation.

Dean was completely lost. He had dove into the lore, searching for anything. Anything he could find on the Empty, on angel resurrection, on the limits of demon deals, on resurrection in general. Whether it was magic, a monster, or hoodoo, Dean was desperate for anything that even had a chance at bringing Cas back.

Jack wasn't much better. He stayed locked up in his room, concentrating. Sam thought he was trying to wake Cas up again, like he accidentally had the first time. But for some reason, it wasn't working. 

Or it had, and Cas was awake, but he had no way of getting back to them.

Sam tried his best. He knew it pissed both of them off that he wasn't obsessing with trying to get Cas back, but he knew better. The angel was gone. He knew that. It was out of their hands.

Sam knew there was nothing in the lore that would help, but he didn't have the heart to tell Dean. 

He didn't feel like telling his brother that he had gone through all the books before, looking for a way to bring Gabriel back. There just wasn't anything there.

The only idea Jack had was that Chuck could bring Cas back. He had done it before, during the Apocalypse, why couldn't he do it again? 

But they had no idea how Chuck had brought the angel back, and he certainly wasn't answering his phone.

So Sam accepted the fact that Cas was gone. If he came back, it would be because he found a way to save himself, like Dean had in Purgatory. Until then, they had to move on with their lives, which was something neither Jack nor Dean wanted to do.

Sam felt like he was failing. He had promised Cas that he would look after them, and yet, Jack was shutting everyone out, and Dean was a silent wreck. 

What else was he supposed to do?

"Dean," He tried again, and this time the hunter reluctantly opened his eyes.

"Hmm?" Dean asked sleepily.

"You fell asleep," Sam offered. Dean blinked, taking in all the books before him with a sigh. "When was the last time you ate something?"

"I'm not hungry," Dean replied, reaching for one of the books.

"That's not an answer." Dean shrugged.

"I don't know. I'm not hungry."

"There's pie in the kitchen." Dean didn't even look up.

"Not hungry." Sam fought back a wince. This was not good.

"Well, don't you at least want to take a shower? Maybe sleep in your own bed? You haven't moved in days."

"I'm fine." Sam sighed.

"Maybe we should get out of the bunker for a while. You and Jack both. Mom found a hunt in Wyoming, maybe we could jump on that-"

"I don't want to hunt." Dean declared. "I just want to find a way to get Cas back, or does that no longer matter to you?" Sam winced.

"Of course it matters," He insisted. "But Dean, there's nothing in these books that can help Cas."

"You don't know that."

"Yes, I do. I've checked."

"Well maybe you missed something."

"No I didn't." Sam proclaimed. "Dean, I can practically recite everything this entire library says on the Empty and resurrection. All the files, everything on the internet, every lore book there is. There's nothing we can do for Cas. It's up to him."

"Well there's got to be something we can do to help him!" Dean retorted. "We can't just leave him there to rot!"

"You can move on," Sam suggested. "You know Cas wouldn't want you to just sit around here and waste away looking for a way to help him that isn't there. He would want you to keep hunting, keep living."

"I can't just abandon him like this, Sam."

"We're not abandoning him. You've tried, Jack has tried. We've all prayed to Chuck nonstop, but he isn't listening. There's nothing else we can do for him. We just have to keep going, and wait for him to find a way back to us."

Dean thought about it. Sam could see the idea working its way through his mind.

"How's Jack?" He finally asked.

"Not great." Sam admitted. 

"We should make sure he's not blaming himself. That never ends well." Sam nodded, thankful that Dean was trying at least.

"So...." Sam went on. "There's still pie in the kitchen, if you want it." Dean forced a half smile.

"Maybe later," He offered.

*******

"Anything?" Castiel asked with a sigh.

"Nothing." Lucifer rolled his eyes.

"A little bit of Jack, and a whole lot of squat." Gabriel proclaimed. "Dear Dad, what I would give for a candy bar right now."

"Maybe there's a way we can force a door open," Lucifer suggested. "Rip one open."

"Against what wall?" Gabriel questioned.

"We don't need a wall," Castiel insisted, pondering the idea. "We could tear a hole in the Empty, like Jack did with the Apocalypse world."

"Exactly." Lucifer agreed.

"But Jack.... The kind of power we would need to do that is enormous." Cas declared. 

"We've got two archangels," Gabriel declared.

"Not enough." Lucifer agreed. "And Michael's still technically alive, so we can't use him. Maybe we could find a way to wake up Raphael?"

"NO." Castiel and Gabriel said in unison.

"Just an idea," Satan declared.

"Wait..." Cas frowned. "Jack's power wasn't just solely angelic. He was half human and half archangel. That's what made him so powerful. So maybe we need a mixture of powers in order to open a door."

"Well, sorry, kiddo, but there's no humans in the Empty." Gabriel offered.

"But there are demons," Cas insisted. "Demons used to be humans. Maybe they could work."

"And what demon could you possible have in mind?" Lucifer said, knowing full well who Castiel was thinking of. The angel smiled.

"The most powerful demon there is." Cas insisted. "Crowley."