Full Summary:

Percy Jackson was the best damn research assistant Tony Stark had ever had. (And yes, we are thinking of the same Percy Jackson.) His life was going surprisingly well - he has an amazing job, he was finally engaged to the love of his life, and the ever annoying monsters had decided to leave him alone. So obviously, something has to go wrong. When Tony flys off on some super secret spy mission, the Gods drop by for a visit - and inform him they have another favor to ask of him, as if he hadn't already done enough. Percy must follow his employer and help a group of so-called superheroes to defeat a magician in a reindeer hat. (Or at least, that's what Percy thought they said.) Forming a genius and perhaps slightly stupid - okay, definitely stupid - plan, Percy does the only rational thing he can think of. He steals one of Stark's suits.

A little background: After the war, Percy and Annabeth finished their last year of high school before heading to New Rome for University. At first, Percy had no idea what he wanted to study, but decided on marine biology. Through some miracle that not even the gods could explain, Percy found he had a natural affinity for all things biology-leading to his eventual degree in bioengineering. Annabeth couldn't be more proud of him. After they finished their degrees, Percy with bioengineering and Annabeth with architecture and civil engineering, they moved back to New York City. Annabeth found a job at a prestigious architecture firm, and is planning to someday open her own firm. Percy was able to get a job as a research assistant to Tony Stark. Thanks to the gods, the monsters have finally left the two engineers alone.

NOW:

Chapter 1:

"Congratulations, Jackson. You're now in charge of the bioengineering department at Stark Industries. Hope you won't mind if I snag you for a couple of odd experiments here and there, though. You were the best damn research assistant I've ever had."

Tony Stark leaned back in his chair, gripping the desk so he didn't topple over.

They sat in his office, walls of glass surrounding them. Secretaries and scientists moved around the surrounding rooms, researching energy and biology and just about anything that Stark Industries could make money on (without making weapons, of course). The wall to Percy's left showed the New York skyline, as beautiful as always. If he looked hard enough, he could find his apartment building not too far from here.

"Now, could you get me some coffee?" Tony put his feet up on his desk, moving his arms behind his head.

Percy grinned. Honestly, he wasn't sure Tony even knew what a research assistant was. "You know that was never part of my job, right?"

A genuine look of confusing crossed Tony's face. "Wait, really? Then who's is it?"

Percy glanced at the personal assistant diligently taking notes in the corner of the room. Tony's eyes followed his gaze.

"Oh! Is that what she does? I thought she just followed me around and wrote everything I did."

Percy raised his eyebrows, watching as the girls cheeks turned rosy red. "Why would she do that? It's not like you do anything interesting." Percy smirked at Tony's fake look of astonishment.

"I do interesting things all the time!"

"Nobody thinks building weird robots is interesting except you." Percy replied. "And Leo." He added under his breath.

He watched in amusement as Tony grumbled to himself about "ungrateful employees" who "are always mean" and "don't even do that good of a job."

"Well, as much as I'd love to continue this, I've got to finish up work before I head home. Annabeth'll kill me if I'm late again, so I really need to go. And thanks for the promotion, Tony. I won't let you down."

Percy finished up his work for the day before heading home to the apartment he shared with Annabeth, Jason, and Piper. It wasn't the largest apartment, with just two bedrooms and a decent sized living and kitchen area. Honestly, he couldn't complain much-the rents in this city were insane and they lucked out. It could get crowded sometimes, but he couldn't have asked for better roommates. Of course he wouldn't be staying there for much longer, as he and Annabeth planned to move into their own apartment once they got married.

Married. He was kind of shocked he had even gotten the guts to propose - a part of him had wanted to just let her do it - but it was all worth it when her eyes lit up and that amazing smile spread across her face, her perfect lips forming the best word in the world: "yes." Piper had taken it upon herself to plan the wedding, so Percy really didn't have to do much at all, which was better for everyone. Although, he did insist on a blue cake.

"Hey, I'm home!" He called into the apartment as he pushed open the door.

"I'm in the bedroom!" Annabeth called out.

Percy made his way to their room, pushing the door open. Annabeth was standing in front of a mirror, clipping her hair up. She caught his eyes through the mirror and smiled at him. Percy's eyes glazed over. Every time he looked at her, she was more and more beautiful. She was wearing a simple dark blue dress, with black high heels.

"Well, are you just going to stand there? Get dressed, the reservation is in an hour."

Percy tossed his briefcase on bed. (As a kid, Percy had never imagined he'd be the kind of guy to carry around a briefcase, but things change-a lot.) He quickly pulled out the suit hanging in his closet and got dressed as Annabeth finished up.

As soon as they were both ready, they headed out onto the street, hailed a cab, and prepared for the infamous New York traffic.

Dinner was going great. They were at a new fancy restaurant downtown, Annabeth was sitting to his right, and his mother and Paul were across from him. His mom couldn't stop gushing about the wedding. Currently, she and Annabeth were discussing dresses, while Percy and Paul were discussing work, sports, and anything not involving frills and bows.

There were no monsters, the food was great, and for once, just once, Percy thought, maybe everything was going perfectly.

Until he got a phone call.

He hesitated before answering, but his mother insisted.

"Percy, I need you at the office. Right now. It's important. Probably the most important thing you will ever do. Are you in your car yet?"

"Uh... what?"

"There's no time to make indistinguishable noises, alright? Call me when you're there."

Percy pulled the phone away from his ear as the dial tone played, confused and slightly angry.

"Looks like I have to go to the office." Percy looked at Annabeth, hoping his eyes showed the disappointment he was feeling at having to cut the night short.

"Should I go with you?" she asked.

"No, no, you guys stay here, continue dinner. I'll call you when I'm on the way home, alright?"

She smiled at him as Percy kissed her cheek before giving Paul and his mother a hug. "I'll talk to you soon, mom."

Percy rushed out the door, hailing a cab.

"Stark Tower, as fast as you can."

It didn't take long before he was in the elevator of Stark Tower, heading up to Tony's Office.

JARVIS had explained to him that Tony had to leave immediately on a private call-which meant he had to go to secret Iron Man stuff-and he needed Percy to help him with something that JARVIS couldn't do.

Percy was kind of shocked, honestly. He had thought there was nothing that JARVIS couldn't do.

He called Tony like he had been told, and Tony launched into an explanation of what he needed Percy for.

"JARVIS has already started the process, but there are a few barriers that a computer can't get past. That's what you'll be there for. JARVIS will tell you what to do when, so you won't have to do much but sit there."

"Okay, sounds easy enough."

"Good."

Percy tucked his phone away as Tony hung up on him. As soon as he reached Tony's floor, he headed straight for the workshop. Normally, no one was allowed access inside except for Tony and Pepper, but JARVIS allowed him entrance. He stalked towards the computers, which were already in the process of... something. Percy wasn't the best at computers, but it looked like JARVIS was trying to hack into something... a SHIELD? Percy didn't know what that meant, but he just hoped Tony knew what he was doing.

All in all, the work he had to do was minimal. Every once in a while, JARVIS would tell him to type in a few words, and then Percy would go back to playing angry birds on his phone. It took about an hour before JARVIS said Percy could go home for the night.

When he turned around and saw a god behind him, he knew he wouldn't be going home any time soon.

"Hello, Lord Hermes." Percy stuttered.

"Percy. It's good to see you."

"Er, you too, sir."

Percy's confusion and anger only seemed to be growing.

"I'm sorry to say this, but... the gods have a request."

Percy stared at him. Was he serious? What could they possibly want from him now?

Hermes ignored the withering glare Percy was sending his way and continued, "It seems there's been a disturbance recently. Long story short, an alien who thinks he's a god has decided he wants to rule the world and use humans as slaves. We can't have that, can we?"

"Uh... no?"

"Right. No. Currently, there's a group of mortals, your boss being one of them, attempting to stop this alien. However, they'll need all the help they can get."

"Okay... and how do I play into this?" Percy really wished the gods would just leave him alone. He had already saved the world twice. He was pretty sure that was a record, and there was no point in trying to beat it.

"Well... we need to you join the group - what are they called? The Avengers? yes - we need you to join the Avengers and stop Loki the alien from overtaking Earth."

"uh... I... What?"

Hermes rolled his eyes. "Join the Avengers. Stop the guy in the reindeer hat. Save the world. Rejoice in getting to live. Got it."

Percy sighed. "And how exactly am I supposed to do that?"

Hermes grinned. "You'll figure it out."

And with that, Percy was forced to avert his eyes as Hermes flashed out before him.

How the hell was he supposed to find where the Avengers where?

And Tony was with them? If only Percy could fly-

Of course. The answer was right in front of him. Literally

Against the wall across from him, was one of Tony Stark's suits.

Tony was so going to kill him.