A/N: Sorry it took so long to update. To be honest, I kind of intended for this to be a one-shot. Then people got all excited about Avengers and reviewed and... well, I had some time off and figured I could wrap this up in a few chapters, so why not?

Disclaimer: I don't own Avengers, Inception, or 500 Days of Summer. If I did, do you think I'd have time to write fanfiction? Hell no, I'd be out there making this stuff CANON!

o-o-o

Dreamshare, as it turned out, was the most incredible thing Tom had ever encountered in his life. Basically, an agent plugged you in, dosed you up, and, as the name implied, you went into a dreamspace shared by anyone else also plugged in. He wasn't exactly fond of the whole needle-in-the-arm bit, but he was going to have to get over that real quick if he wanted a job, since Vance or Coulson… Phil. He could stick with Phil. Since Phil had been courteous enough to quit Tom's job for him.

"I don't get it," Tom said, gingerly poking at the machine with all the needles. "You've got a whole building swarming with agents. Why do you need me? And why didn't you need me when I actually worked for the greeting card company?"

"Frankly, Hansen, you needed to grow up before we tried to recruit you."

Yeah, that stung, by the wasn't going to argue. A proper adult probably wouldn't have reacted that strongly over a breakup with a girl he'd been dating less than a year.

"Okay," he assented. "So why do you need me now?"

"New tech, new needs." Phil nodded at the machine. "The dream needs a single, steady mind to hold it together. We need an architect to design a landscape that suits are needs, and remains simple enough that the dreamer doesn't forget details halfway through."

"And that's my job? Designing it?"

"You'll even get a Christmas bonus."

As it turned out, designing dreams was like night and day to designing buildings. For one thing, he didn't have to worry about pesky things like airflow or too much light coming in through a window. In dreams, people tended to fill in those gaps themselves. He also didn't have to follow the rules of reality. Hell, he could Scooby-Doo this shit up if he wanted to, with secret trap doors behind paintings and hidden stairwells that led down ten floors in a single flight. All the paradoxes he'd sketched I times of boredom could become an almost-reality in a dream, and he relished every second of it. The techs started teasing him about living more in the dream than in reality. Maybe they had a point. In the real world, his friends were on his case about being a slave to his job.

"I get that you got your heart broken a couple of times, but you can't marry your work."

If only they knew.

After two months of playing with the dream-machine –PASIV, Phil had called it-, Tom had enough track marks on his arms to look like a severe heroin addict. He took to wearing shirts past his elbows, even on his days off, just to hide it. Still, for the chance to build the impossible, it was worth it. He was almost giddy when Phil informed him that it was time to start testing Dreamshare on active agents.

A team of three men and two women, all dressed in S.H.I.E.L.D. black, came into the lab, each eyeing the PASIV as suspiciously as Tom had upon entry.

"Don't quite see the point of this, sir," one announced, crossing his arms. "Last time I checked, I didn't need more training."

"Get your ass in the chair, Barton," Phil rebuked with the weary tone of a man who's had to reprimand his agent one time too many. "That's an order."

Agent Barton shot Tom another suspicious glance and settled down in his chair. The remaining agents did so with considerably less fuss.

Tom plugged himself in and settled back in the most comfortable position possible. The timer was set for ten minutes, meaning two hours. Let's see what he could do in two hours.

Phil's hand hovered under the plunger. He glanced down at Tom.

"Give 'em hell, Mr. Hansen."

"My pleasure, Mr. Vance."

Phil's lips quirked in amusement. He depressed the plunger, and Tom sank down into the dream.

He awoke on a rooftop in a crumbling city. The agents popped up here and there, some in the decrepit upper floors of nearby buildings, others on the street. One agent was positioned on the corner of the rooftop; Barton. His standard issue S.H.I.E.L.D. uniform had been replaced by a tight, sleeveless black and purple body armor. Draped over his back was not the gun Tom had expected, but a bow. Tom quirked a brow.

"Didn't know S.H.I.E.L.D. hired Robin Hood," he remarked.

Barton turned to look at Tom out of the corner of his eye.

"You wanna be a more active part of this exercise?" he challenged.

"You can't take me out, dude, the dream'll fall apart."

"Looks like it already is," Barton scoffed. "What's with this architecture, huh? Fan of 28 Days Later?"

Tom smirked and settled in an aging armchair he'd dreamed up.

"Something like that," he offered.

"What are you… holy-"

Barton whirled around and proceeded to fire arrows down into the throng of zombies. Radios buzzed with static, and like a well-oiled machine, the agents proceeded to take out his undead projections. It was a thing of beauty, really, how well they all really did work together. Seeing it in person, even if was a dream, was about a thousand times better than any action movie.

At least until the zombies began to overwhelm the S.H.I.E.L.D. agents. One by one, the agents were slaughtered, and Tom had to wince in sympathy. By his calculation, there should have only been about twenty minutes until they timed out of the dream. Hopefully the remaining agents would change their tactic and just try to survive.

"The hell, Hansen, you gonna help?"

"Uh… sorry. Not supposed to." He really wasn't. This was a training exercise, nothing more. For all the trapdoors and secret tunnels he'd built everywhere, he wasn't allowed to tell anyone about them. Seemed like a damn waste in his opinion.

"Are you shitting me?" Barton exclaimed. Tom shrugged.

"Well, it's protocol."

"Screw protocol!"

"But Phil said-"

"Screw Phil with a big-ass railroad spike, Hansen!"

Tom tried to come up with something to say to that –or at least get the mental image out of his head before it popped up in the dream somewhere- but the zombies began to climb vertically up the side of the building. Tom shifted in his seat and sucked in a sharp breath. He had to remind himself that they were technically his projections, so he wasn't in danger himself.

Barton, however, didn't look particularly amused. He had only a handful of arrows left, nowhere near enough to take out the remaining zombies before they killed him. Still, he nocked an arrow and spun around, aiming it at Tom.

"What-"

But the arrow pierced his head, right between the eyes. There was a sharp stab of pain, a blinding light, and then-

Tom started in his seat, his stomach rolling painfully. He had only enough time to turn over before vomiting right onto the stark white floor. Over the pounding of his heart, he could hear the dismayed moans of the lab techs, and the chuckles of the agents.

Barton stretched in his seat and sat up, smirking at Tom.

"If you're gonna dream up battles for us," he said. "You gotta learn a thing or two about being a soldier."

And that was how Tom entered into his practical training. He tried to fight against it at first. He was just an architect, he was a civilian, he'd never held a gun in his life. Barton didn't care and, after a word with his superiors, neither did Phil. So Tom had his orders. The shooting range it was.

In the real world, his friends went on with their lives. Some got married. Some got promotions. Some moved away and had adventures, and every one of them seemed to think Tom was rotting away in a sub-par architectural firm. Every now and then he still went home for family dinner. If he remembered. His sister had a new boyfriend and dyed her hair blue. They talked about work, school, what was happening on tv. Tom couldn't come up with anything much to talk about.

He learned the difference between a sniper's weapon and a foot-soldier's weapon, what sort of position was ideal for a given situation, and how a team really set up. More than once, he went down into the dreams as one of the soldiers, just so he could build them better scenarios. He died a thousand times over, each death more creative than the last. It never really got easier, but at least he didn't wake up vomiting.

Before he knew it, a year had passed. It felt like no time at all. Maybe it was the dreaming. He didn't dream naturally, anymore, and with the lucid dreaming, it felt like he never really let go anymore.

One day, it hit him like an anvil. He woke up in his bed, which felt less familiar to him than the lounging chairs in the lab, and realized he wasn't really Tom Hansen anymore. Tom Hansen was a skinny guy, drifting between boy and man, hung up on all the petty distractions of everyday life. He was stronger, faster, sharper, and more focused than he had ever been before. His friends had dwindled to fond acquaintances. His family was just a group of people he loved, but could no longer truly identify with anymore. Tom Hansen didn't know the first thing about guns or warzones. He'd never gone a whole year without being hung up on some romantic notion.

So, quite simply, Tom was no longer Tom Hansen. He didn't really know who he was, but he knew for sure that he needed to go ahead and move out of Tom Hansen's apartment.

It wasn't as difficult as it should have been. Over the last year, he'd slowly been ridding himself of unnecessary junk. Most of his wardrobe was no longer useful to him. His drafting supplies were inadequate compared to the stuff S.H.I.E.L.D. had to offer. And did anyone really need that many coffee mugs? Seriously? What had he been thinking?

He moved into one of the apartments under the greeting card company with only a few of boxes of personal belongings and several garment bags protecting his suits. He took one of his days off to settle in, maybe plug himself into a PASIV to try out a few new paradoxes that, to be honest, the training simulations really never gave him the chance to try.

Phil stopped by, dressed as Mr. Vance, and knocked on the door.

"I hear you moved in," he remarked dryly.

Tom gestured at his now occupied apartment.

"Guess you heard right."

Phil nodded and slipped his hands in his pockets.

"Just wanna warn you to be careful, Hansen. This kind of work will take over your life. We all need something outside of it, even if it's just an apartment."

"Or a greeting card company?"

Phil shrugged.

"Or that. Get some fresh air, will you? We're bringing in a team of architects from France in the morning, I want you rested and ready to receive them."