A/N: Have guys seen Iron Man 3 and the finale of the Vampire Diaries season 4? They are both bloody awesome! I am so happy, I am updating! So here you go, the Avengers spring into action and Katherine tags along.

Enjoy!

Chapter 7

Steve was not happy. He had voiced his reservations against his tutor boarding the jet plane with the team until she had reminded him that it was also her job as their supernatural consultant. Fury had approved her presence on board much to his annoyance.

"Ease up, Cap." Katherine said with a wink. "I am not going to set foot outside this plane if that makes you feel better."

His jaws clenched as he muttered. "I'd feel even better if you were safe back at Stark's tower, Katherine. This is no place for someone like you. It's not safe."

Despite herself, her gaze softened. "I'll be fine, Steve."

"Hate to break up the moment, you two." Clint called from the pilot's seat upfront. "But we're approaching Central Park. So far Tony has spotted a pack of twenty Chitauris cornering civilians in the Pulitzer Fountain area. He's taking out as many as he can but they are overwhelming him."

"Where are they coming from?" Natasha wondered.

The trees of the park were making it difficult for them to track the aliens' movements but they could make out their sleek forms racing through the woods towards the fountain. A red and gold figure leapt into the air, firing rapid shots before landing amidst the aliens' lifeless bodies. People were running and screaming as the aliens moved in on them.

"Help would be great right about now, guys!" Tony yelled over the intercom.

"Shit…" Clint muttered as an alien viciously landed atop a man, killing him with a quick stab and jab motion of their weapon. "Your orders, Cap?"

Having witnessed the same scene, Steve's resolve strengthened. "Natasha, you'll provide air support. Create a perimeter and keep any more Chitauris from getting in. Banner, you're with me. Take out the groups, scatter them. I'll take out the stray ones. Clint, guide the civilians to the nearest exit." he ordered, his role as natural leader taking over. "Katherine, stay here with Natasha. Let us know if you pick up anything supernatural."

Katherine was impressed as everyone quickly fell into their respective roles, following Steve's lead as the plane deposited them in the middle of the battlefield. Bruce with an impressive roar, turned into the raging green beast that proceeded to effortlessly pulverise the close-quarter attackers. There was no resemblance of the group of misfits she had come to know over the past two days but rather a well-oiled fighting team.

"Best you take a seat." Natasha said suddenly while manning the guns that turned away approaching Chitauris. "Wouldn't want you to get hurt now or the Cap will have my head."

If it wasn't for her super sense of balance, Katherine would be rolling around the plane by now but as it were, she dropped down into the seat Clint had just vacated.

"Is it normal for the Chitauris to attack humans?" she asked as another human was killed.

"Yes but not in this manner. The Chitauris have a soldier-like mentality in battle but this is…savagery." Natasha said.

Almost predatorily, Katherine thought. It's like they were hunting humans for…some reason...

Providing cover wherever he could, Tony shot through the air like a missile, swiftly removing their opponents from swarming Steve who fought those foolish to take on him.

"They just keep coming!" he complained.

"Sir, there is a bank robbery taking place on 86th Street, Upper East Side." JARVIS said.

"A little busy here, JARVIS." Tony retorted. "Call the local cops. They should be free."

"Sir, video feed from the bank indicates the robbers aren't human. Furthermore, I've identified one of the robbers as Amanda Johannes. She dates back to the 1940s, Berlin."

"Huh." Tony blinked. "Katherine will be thrilled. Give me a count of their numbers and patch me to the rest of the team."

"Yes, sir." a static buzz indicated his line was opened to five others.

"Bad news, ladies and gentlemen." Tony announced as he zipped past the battlefield, his repulsors firing. "JARVIS just called in a bank robbery happening now. Vampires and possibly werewolves. I am going to check it out. Think you can handle it here?"

There was a thunder and a crackle in the air as a storm cloud gathered over the park indicating the arrival of someone before Steve answered distractedly. "Yeah. We'll manage. Backup is on the way."

Tony hesitated. "And I'll need Katherine with me on this."

Steve didn't like it but as Katherine had reminded him earlier, it was still her job. "Alright. Natasha, go with them and Katherine, don't –,"

"I got it! Don't leave the plane." the other female said in exasperation.

"Let's go, ladies." Tony said, zipping off quickly, trusting Natasha to keep up with him.

The plane took off just as a shot of lightning created a crate in the ground, killing a number of the aliens that tried to climb on board. A red-caped figure landed right smack in the center, forming a barrier between the aliens and Clint who was ushering people towards the exits. The arrival of a god was enough to make the Chitauri forget the plane and go after him instead.

Steve managed to get in one more line before his attention turned back to the fight. "Tony, take care of her."

That was an order and one that wasn't to be disobeyed. Then there was only silence on the other end. Tony sighed. Life would be so much easier if Steve just knew that one tiny detail about Katherine being, well …not human.

"Alright, JARVIS. Give me the video feeds."

"There appears to be six robbers, sir although I can't get a heat reading from three of them."

Several video displays appeared in his view, one focusing on a blonde woman holding a briefcase. A security guard rushed her only to be sent flying into a wall a second later. She barked orders to three men and two women that began hustling hostages towards the main entrance. A fleet of police cars had surrounded the building but Tony sensed things were about to go down badly soon.

"Agent Romanoff, you seeing this?" he asked.

They were rapidly approaching the location and needed a plan to diffuse the situation soon.

"Yeah." Natasha replied. "I am. Looks bad."

"Understatement of the year." Katherine joined in, staring at the blond. "Stark, that's her."

"Got it." Tony muttered. "Any idea why she would be robbing a bank?"

"Nope. But I am thinking the attack on the park was a distraction. This must be important." Katherine said.

"Well, then. Let's crash the party then."

They arrived in time to witness things turn for the worst literally. As soon as the hostages were through the door, three of the robbers transformed right in front of them and the police, taking on a form that was faster and deadlier. Their howls penetrated the night before disappearing into snarls as they leapt at the police men. Guns were fired but the werewolves were faster and stronger, taking and shaking off hits as though they were nothing. One of them flipped a police car aside forcing everyone to take cover as it descended on them.

A repulsor shot from Tony blew the vehicle to bits and a second shot struck the beast in the chest, taking it off balance. Iron Man landed hard on it and socked a punch to its face, dislocating the lower jaw. A beep from JARVIS warned him of two more approaching before one tackled him off its unconscious partner. The werewolf flung him through the air, sending him crashing through the wall of the bank.

"Ugh. Son of a –,"

"Stark!" Natasha barked in warning as the plane let out a string of bullets to keep the werewolves from going after the downed billionaire.

From the corner of his eye, Tony noticed one of the vampires lifting something huge to their shoulders. Shaking stars from his head, he realised it was a –

"Agent Romanoff!" he sprang to his feet as the bazooka fired a missile at the jet. "Heads up!"

She was already manipulating the plane to evade but the missile struck the left wing, sending it careening off balance. The vampire reloaded the bazooka again, preparing for fire but Tony fired a shot at the vampire, knocking him aside.

Natasha managed to emergency-land the plane in the middle of the street without running over any cops or civilians, a testament to her piloting skills. A quick glance told her that the situation has yet to improve for the remaining two werewolves had turned on the hostages and were sinking their fangs into them. Opening the hatch, she prepared to join the fray before she remembered her passenger.

"Stay here." she snapped at Katherine. "Don't you dare set foot outside this plane."

Before Katherine could retort, Natasha was on ground, her guns in hand. She fired at the werewolves' faces, aiming for their vulnerable spots and forcing them away from the people.

"Get out of here!" she shouted, waving away the humans who scrambled and limped their way to safety.

As the remaining hostages cleared the area, she turned her attention to the blond-haired vampire standing at the entrance of the bank, the briefcase at her side. The woman made a hand gesture and another vampire in a business suit leapt at her. Instinctively, she dropped on her back, flipping the over-sized man over her before springing to her feet.

"Wood. I need wood." she muttered, remembering what Katherine had said about vampires.

"Why, Agent Romanoff, I never knew you were that deprived." Tony remarked as he slammed, shoulder first, into one of the werewolf.

Rolling her eyes, the assassin kicked up a loose wooden debris from the ground, snapped it over her knee and voila, instant makeshift stake. She tested its weight as her opponent rose and before it could properly recover; she pulled her arm back and sent it rocketing at him. It struck him in the chest, eliciting a scream of pain as he staggered forward. Natasha held her breath briefly as the creature collapsed, its body turning into a corpse.

"Nicely done, Agent Romanoff." Tony said in the middle of his struggle with a werewolf that was trying to rip off his helmet. "But our main mastermind is getting away."

Natasha whirled around in time to see the female bounding down the steps with swift movements, heading for the drain hole. The remaining cops opened fire on her but she merely tore open the man hole and flung it at them like a Frisbee, sending them scattering. Casting one look at the Avengers, the woman dropped straight down into the hole, briefcase and all. Then to Natasha's horror, she noticed someone else in pursuit of the blond.

"Katherine!" she shouted, drawing Tony's attention. "Get back here!"

Tony kicked away the werewolf and unleashed two shots on it, propelling it away from him and hopefully killing it in the process. A glance at the manhole told him his suit would not fit in there without city damage. What more he couldn't just leave Natasha here alone to take on a werewolf and a vampire. Torn, he opted for the most efficient method.

"JARVIS, track the homing device on Katherine's bracelet. Keep me updated on her location." he ordered as he fired a missile at the last remaining werewolf.

~.~

Amanda was pissed beyond reasoning. It was supposed to be an easy job. Breaking into the vault, steal the stones, turn a few hostages into werewolves, set them loose on the police and escape. She had anticipated the Avengers interfering but not so soon. Something must have gone wrong with the distraction. Running through the sewer was not her idea of fun but it had been the best way to escape Iron Man and the assassin.

But what peeved her the most was that Katherine had been there. She had heard the assassin shouting the other woman's name as she fled and it had taken Amanda a while to lose Katherine in the sewers. She wanted to kill the other vampire but not when she had her precious cargo.

"You're late."

Her green eyes narrowed as she emerged into the warehouse and glared at the Chitauri in disguise. "Your forces didn't exactly do their job right. I had two Avengers to deal with!"

"The unexpected arrival of the Asgardian god took our forces by surprise but we were able assimilate with several humans and the Avengers are none the wiser." Zarkis said, his face displaying his annoyance. "And were you not able to obtain the stones?"

"At the cost of several of my men." she said sorely, hurling the briefcase over to them. "The only known heirloom of the Bloody Nicholas, the last Emperor of Russia. This better be worth it."

"It will be." her accomplice said, catching the bag with ease. "They will. Rest assured Amanda, the sacrifice of your men will not be in vain."

"Need I remind you again that your forces failed to distract the Avengers? I lost five of my men, three of which are werewolves!" she said, scowling. "Obedient werewolves aren't easy to come by for your information."

"Amanda, my Lord Thanos will reward you handsomely for your aid." he said. "Now, it's time to move on to the next part of the plan."

"Do what you must. I have a vampire to hunt." Amanda said darkly before retreating back into the sewers.

The Chitauri-disguised-as-a-human started to open the briefcase when the sound of heels clicking against the floor drew their attention. He drew a spear, the blue hue lilting up the darkened warehouse as a dark-haired woman stepped into their view.

Unaffected by the glowing weapon charging up to fire, Katherine smirked. "You know she's just going to betray you once you have given her everything she wants."

"Katerina Petrova. We have heard of you." the spear-wielder said. "Amanda is most adamant of your demise. Perhaps I shall fulfill her wish right now."

"And risk incurring the wrath of the same team of superheroes that beat your army before? Please. Go right ahead." she sneered. "You kill me and it's not going to be pretty for you. Alternatively, we can do this the less violent manner. You can listen to my proposition."

That caught his attention and he lowered the staff. "Interesting. You would deal with the enemy for the lives of your team?"

"They are not my team." she corrected him. "My proposition is simple. You want the Avengers out of your way so that your master can take over the world. I want Amanda and Klaus off my back permanently. Do you see where I am going with this?"

"I am intrigued. Continue."

"I have no interest in what you're up to nor do I care that this city is going to be turned into a warzone once more. Once it starts, I am out of here. I just need to know when." Katherine said calmly as she began walking towards him.

"And how will I know you won't betray us?"

"You don't. But at the moment, I am the only one that team of misfits will listen to." she said, reaching out and touching the tip of his weapon, unafraid. "Because they don't have a choice. You get Amanda and Klaus off my trail and in exchange, I'll give you the Avengers, starting with Captain America."

A/N: Have I mentioned how much I love Katherine? Please read and review!