Disclaimer: I do not own the Avengers or Supernatural

The interrogation room was small, and dimly lit. The walls and floors were a dark indigo, with a hexagon pattern imprinted on the surface. In the middle of the room stood a metal table and two chairs, one of which Dean was currently seated on. His wrists were shackled, and an agent stood behind him. Dean wasn't willing to admit it, but he wasn't going anywhere, anytime soon.

The director of S.H.I.E.L.D., Nick Fury, sat in the chair across from him. He placed a file on the table, which Dean assumed was his. Dean couldn't help but notice the worry in the director's expression. But perhaps it was only for show.

Fury made eye contact with Dean, and hesitated. With a small sigh, he opened the file. Dean strained to read the file upside down. He frowned. It didn't have anything to do with him, not that he could tell anyways. There was an image of what Dean would call a cosmic cube. It seemed to be composed of a sort of blue energy, similar to flames. Right out of a comic book, Dean thought with a small smirk. Though he couldn't see what he had to do with an object like that.

"We're facing a global catastrophe, Mr. Winchester." The director informed him.

Dean scoffed, unable to help himself. "So were we." He reminded Fury.

"Oh, I almost forgot." The director responded, rolling his one good eye. "Your evil twins, right?" Dean clenched his fists. "You know, I haven't seen them since we took you in."

Of course not, Dick Roman was too cautious for that. No, their operation was probably running smooth as ever. Unless Bobby had figured out a way to stop them. Dean cleared his thoughts. Now was not the time to think about Bobby or Leviathans. Whatever Fury wanted, he had to face head on.

"Wouldn't have expected you to." Dean replied. "It would be a dumbass move on their part."

"Perhaps. Let's put aside this conversation for now, believe it or not, that's not why you're here." The director paused. "We've made some mistakes."

Dean rolled his eyes. "No surprise there."

"An artifact of great importance was stolen a few days ago, and we need help tracking down, and stopping the thief." The director continued.

"What's the big deal?"

"It has the potential to wipe out the planet." The director replied. "We're putting together a team, and you're name came up."

Dean smirked. "Desperate are we?"

"Very."

"Let me guess, the object in question is that cube?" Dean asked, eyeing the file.

The director nodded. "As a matter of fact."

"What's in it for me?"

The director smiled. "A chance to be the hero for once in your life."

Dean scoffed, restraining himself from making a comment he'd only regret. "I'll work under one condition."

The director raised an eyebrow. "And that is?"

"You put Sam on the team too. Believe me, he's an asset."

"Alright, I accept. But both of you will return to your cells when all is well again."

Dean froze, realizing what the director was saying. He and Sam would go right back to solitary confinement, never to see each other again. He couldn't let that happen. Not to Sam. "No."

The director raised an eyebrow. "No?"

"I'll return to that hell hole you call Ryker's, but Sam walks free."

The director was taken aback, and he stared at Dean, no doubt trying to figure him out. "You'll throw away everything for your brother?"

Dean shrugged. "Yeah, well, I guess it's a Winchester thing."

Hours later, after an alarming flight via quinjet from Ryker's Island, Dean stood waiting on the bridge of S.H.I.E.L.D.'s main base of operations; the helicarrier. Which, to Dean's relief, wasn't in the air. Yet.

He wasn't alone though. Dean doubted the helicarrier was ever completely empty with the number of agents running the day-to-day business of S.H.I.E.L.D. There was one agent, addressed as Agent Morse, whose assignment was to watch his every move. She stood still as a soldier, and reacted to every movement he made, her hand instinctively reaching for the gun at her hip. She didn't have patience for any of his shit either. In fact, she was the reason he'd been unconscious for half of the flight.

"Dean."

Dean froze, recognizing the slightly hoarse voice. He turned slowly and faced his baby brother. "Sammy." He whispered.

The two brothers embraced, and Dean fought the urge to cry. Dammit, he was thirty-three years old for crying out loud. But he couldn't help shed a tear or two. He hadn't seen Sam since the week they were apprehended. While he had been sent to Ryker's, Sam had gone to Alcatraz. The two of them had been apart for so long, but it was all worth it just to see Sammy's smiling face again. Dean smiled, he had his brother back.

Sam pulled away, and grinned. Dean placed a hand on his brother's shoulder. "You ready to save the world, Sammy?"

"Yeah."

The smile slipped off Dean's face as he felt the ground shift beneath them. He watched out the large window as the helicarrier began its ascent into the sky. Sam snickered as Dean clenched his fists and hummed a few notes of Metallica's 'Enter Sandman'.

Sam patted Dean on the back, and chuckled. "Some things never change."

"Gentlemen." Nick Fury greeted, approaching them.

Sam and Dean turned, realizing two other men had joined them. Due to their lack of uniform, Dean assumed they weren't S.H.I.E.L.D. agents. Maybe they were part of the team the director had spoken of.

The one man, a tall blonde in a leather jacket, walked up to Fury and handed him a dollar bill. Dean scoffed. "Lose a bet?"

"None of your concern." Fury responded, eyeing Dean. He threw his hands up in mock surrender.

Sam elbowed his older brother. "Don't push it." He whispered.

"Thank you for coming."

Dean was about to reply with a snarky comment, until he realized the director wasn't speaking to him. He was speaking to the other man. Dean watched the two shake hands.

"Thanks for asking nicely." The man looked around nervously. "So, how long am I staying?"

"Once we get our hands on the tesseract, you're in the wind." The director replied.

"Where are you with that?" The man replied.

"Yeah, where are you with that?" Dean echoed, receiving a glare from the director.

Sam glanced between director Fury and Dean. "Dean." He whispered. "Don't piss him off."

"Might be a bit late for that warning, Sammy."

Sam rolled his eyes. "Yeah, I see that."

"We're sweeping every wirelessly accessible camera on the planet. Cell phones, laptops… If it's connected to a satellite, it's eyes and ears for us." Another agent replied.

"That's still not gonna find them in time."

Dean's head snapped in the direction of the female speaker, and he saw Sam shake his head. She was out of uniform, but the way she held herself, she was obviously another agent. Man. Dean thought. She's hot.

"You have to narrow your field." The second man said. "How many spectrometers do you have access to?"

"How many are there?" The director asked.

"Call every lab you know." The man instructed. "Tell them to put spectrometers on the roof and calibrate them for gamma rays. I'll rough out a tracking algorithm, basic cluster recognition. At least we could rule out a few places. Do you have somewhere for me to work?"

Fury nodded. "Agent Romanoff, could you show Dr. Banner to his laboratory, please?"

Agent Romanoff, the female agent, began leading the second man, Dr. Banner, out. "You're gonna love it, Doc. We got all the toys."

"We done with all the tech stuff now?" Dean questioned. "Cuz I want to know where we come in."

The director grinned. "For now, let's call you plan b. We'll let you know when we require your assistance."

Dean rolled his eyes as the director left. Now, it was just him, Sam, the other agent, and the blonde.

"Alright, so let me get this straight." He said, breaking the silence. "We've got the female agent, the smart doctor, eye patch just left. So, where do you two come in?"

"My name is agent Coulson." Agent Coulson turned to the blonde, a smile lighting up his face. "This here, well, he's a living legend."

Dean scoffed. "A living legend?"

"Yep. Captain Steve Rogers."

Dean furrowed his brow. "Who…"

Sam's eyes widened. "Captain America?"

Coulson nodded. "The one and only."

A/N: Hope you enjoyed the first chapter! There should be many more to come! Thanks for the reviews, favourites, and follows!