Author's Note:
The following events take place during the first Avengers movie.
Most of the movie's events remain the same unless otherwise stated, though I may reorder some of the chronology for the sake of pacing. I jump around through the story so this works better if you remember the movies well.
Of course, Marvel owns all the rights to these characters, and there will be spoilers for the films involved.
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For the first time in what felt like weeks, Natasha felt like she had a clear head. As she strolled across the Helicarrier's runway, the cool sea air made her feel fresh and ready for whatever trouble the day was likely to send her way.
It didn't hurt that last night's... activities... had released a tension in her body that was interfering with her work. If she hadn't sorted that out, she wouldn't be on her top form today. It might have been a slim justification, but it was enough to keep her feeling positive about the whole thing.
If it wasn't for the rest she finally achieved last night, she might be a little freaked out that she was about to meet one of the most important men in history.
She arrived just as Coulson was disembarking the quinjet, looking like he was trying his best to remain cool and casual, holding all his fanboy excitement inside. Next to him was none other than Steve Rogers, better known to the history books as Captain America.
"Agent Romanoff," Coulson stated, as the super soldier's eyes wandered around the impressive airship, "this is Captain Rogers."
"M'am," Rogers stated, addressing her as properly as she imagined someone from the 1940s would.
"Hi," she bluntly replied, before telling Coulson he was needed on the bridge. He left her to escort his passenger the rest of the way - but they had one more team member to pick up first.
"There was quite the buzz around here, finding you in the ice. I thought Coulson was gonna swoon. Did he ask you to sign his Captain America trading cards yet?"
"Trading cards?"
"They've vintage, he's very proud."
They came across Bruce Banner, who was nervously side-stepping the countless S.H.I.E.L.D. staff preparing the strip. Rogers immediately approached the doctor, asking him questions. Natasha let them have their moment, knowing from Banner's darting eyes that he wasn't entirely sure how to speak to her after their last confrontation.
"Gentlemen, you may want to step inside in a minute," she eventually interrupted. "It's gonna get a little hard to breath."
The Helicarrier started to shake, its innumerable moving parts creaking as it prepared for take-off. She couldn't help but smile as the two men, who had seen the most strange of scientific advancements, were stunned by the turbines rising from the water.
When they arrived on the bridge, they found hundreds of agents sweeping every wirelessly-accessible camera on the planet, with anything connected to a satellite at their disposal. But it was a slow method of finding Loki, and they needed Banner to speed up the process.
Luckily he had some ideas for tracking the tesseract, so Fury asked her to escort him to his lab so he could get down to work. She followed the orders promptly, though she was slightly put off by the glare Hill was giving her from across the room. 'I knew that latte comment was going to bite me in the ass,' she thought to herself.
"You're gonna love it doc, we have all the toys," she remarked, not making eye contact as he led him down the hallway. The short walk was silent and a little awkward, but Natasha didn't let it show. Eventually, Bruce spoke, though she didn't have time for the chit-chat.
"So... about Kolkata -"
"I'm going to stop you right there, doctor. We don't need to talk about it. It's in the past. We're all good."
He hesitated, and by time he went to speak again they were at the entrance to his lab, and she gestured to the door for him to enter.
"Go save the world."
*****
Natasha only had time to quickly grab a bite to eat before she found herself summoned once more. Banner's algorithm had found Loki extraordinarily fast, as it seemed like the villain wasn't hiding at all.
It turns out he was walking around in public, in Stuttgart, Germany. Rogers was already on route to intercept him before anyone else got hurt, and it was Natasha's job to provide a little back-up.
The situation was far from stable, as she soon found out. Cap was severely outgunned by the Asgardian, and with no clear shot she had felt pretty helpless during the encounter. Of course, that's when Stark made his dramatic entrance, taking over her PA system to blast out AC/DC's 'Shoot to Thrill' and taking down Loki in a single shot.