A/N: AGE OF ULTRON SPOILERS. SPOILERS SPOILERS SPOILERS.

This AU assumes Bruce/Natasha didn't happen. As a result, it's still in line with the fanon of my other stories.

This one-shot exists because Bruce/Natasha was unbearably forced, because Black Widow doesn't need to be rescued by all the men in her life, because she might see herself as a monster but it isn't purely because she can't have kids, and because I love this movie anyway, and I wanted to write what I felt it had the potential to be. So there.

throw away the key (to who I used to be)

She wakes, and the air is thick, an assault of metal and oil. She's lying on her side, her ribs aching, her heartbeat ever so loud in her ears. Slowly, she opens her heavy eyes.

She's in a cage.

The reality of it registers dully, because her mind is an interconnected network of cages all its own, and having one appear in the world outside of her head is jarring to the core. She grips the bars until her knuckles go white, and the pain sends it all crashing back, falling and metal and dark —

She's in a cage, and she's Ultron's prisoner.

Screw that. She is Natasha Freaking Romanoff, and she is not the damsel in distress, wailing and weeping in the clutches of Tony's aptly named Murderbot, waiting for the Boys Club to come save her.

Except... the cage is locked, the key is nowhere in sight, and her only available resources are her own two trembling hands. Freaking fantastic. When this is over, and it will be over soon (nothing lasts forever,) she's going to beat Clint within an inch of his life for this.

A shadow shifts. Natasha turns, braced to defend herself with her very fingernails if need be. Ultron looms on the other side of her cage bars.

"Well, it seems we're past negotiation. Somehow I'm not surprised, given the man who designed you." Natasha plants her hands on her hips. "So tell me, Ultron. Why haven't you killed me?"

Ultron laughs — a harsh, echoing, robotic sound without a trace of humor. "You and I, Widow... we are very much alike."

She grits her teeth. "I'm nothing like you."

"But you are," says Ultron. "You look at this planet, only one of many, and you see its beating heart. Beating for what? There will be nothing left when the Avengers are finished. They want to save the world like it has a soul, but you've never needed a savior, and you forgot about your soul a long time ago."

"Don't tell me about my eternal soul," Natasha snarls. "You're a machine. You shut down, you're broken into spare parts, and you're nothing. You're only what Stark made you, and he can tear you apart whenever he likes. You're a weapon — that's your beginning and your end."

"And what are you, Widow?" It feels like the breath has been punched from her lungs, but her marble expression doesn't falter. "You understand that to live, you have to change. Sometimes you have to kill." Ultron shakes his head. "Don't pretend to regret all that red in your ledger. You might like to wipe it out, but you would still write it again."

Natasha swallows hard.

"You want to be upgraded into someone unbreakable." Ultron's eyes flash like torches in the dimly lit chamber. "And you're willing to paint the world red." He closes one metal hand around the bars of her cage. "So am I."

Natasha takes a sharp breath. "I am nothing like you."

"Ah, perhaps we are different in one way. You can never create new life. But I..." Ultron throws his head back towards the sky, and above him, numberless metal skeletons stir in the shadows, shift along the rafters, raise their heads from every crevice of the walls. A metal army, born of hatred, not love. "I have my children."

Natasha surges forward, grips the cage bars with both hands. Her lips pull back from her teeth. "Go to hell," she screams.

"Hell is already here, Widow," Ultron says, his inhuman face filling her whole vision. "I'm going to build heaven."

Natasha's lower lip quivers. "How?"

"By beginning anew. Isn't that what you've always wanted?"

"If you haven't killed me yet, I assume you have use for me."

"I might be the greatest intelligence on this planet, Widow, but I'm not a warrior. You are." Ultron crosses his arms across his metal chest. "Imagine an army built from an assassin's template. Imagine metal soldiers with the instincts of your long, long lifetime of training." His voice was full to the brim with a scientist's wonder. "Imagine your mind melded with mine, multiplied a hundredfold."

"You want to use me for your next wave of soldiers."

"I want you at my side when I put hell's fires out. I want you to help rule the world we construct from the ashes."

A small smile curls Natasha's lips. "Starting over."

"Your ledger wiped clean."

"You'd do that for me?"

"Sentiment is a sickness," Ultron says. "I would do it for the new world. It needs people like you — more than human, more than tangles of veins and hopes and sympathies. It needs weapons like you. Like me."

Natasha cocks her head. "So you'll let me out of here?"

Ultron drops to one knee, so that they are eye-to-eye. "Are you ready to build an army, Widow?"

"I was designed for it," she says, and even as the words escape her lips, Ultron crushes the cage lock in his metal fist. She steps over the threshold, head held high, while he looks on in muted wonder. Sighing, she meets his eyes. "Ultron?"

"Yes, Widow?"

And like Loki, like Stark, Ultron has fallen directly into Black Widow's web.

She crouches down and then leaps in one fluid movement, her legs locked around his head, her teeth bared. He screams, but it's not a human sound, and when he tries to tear her off, she arches out of his reach, her spine curving gracefully. A dancer's defense.

"I don't need a soul," Natasha says, "to know the world's worth saving."

She flicks her arm to release the concealed shock device in the sleeve that Ultron, for all his supposed genius, never bothered to check when he confiscated her other weapons. It's the same weapon she used to temporarily disable the Winter Soldier's arm during their fated confrontation. The small disc attaches to Ultron's shoulder.

"And I don't need your salvation," Natasha says, as Ultron collapses heavily to his knees, "from who I used to be."

The paralyzing shock will only last for two minutes, at best, but Natasha can be a speed demon when she needs to be. She sprints out of the warehouse and straight into the Sovakian city, where she breaks the window of the first electronics store she sees. It takes approximately forty-three seconds to assemble a makeshift beacon. Without stopping to apologize to the shopkeeper, she launches headlong back through the shattered window. And finally, every breath splintering through her ribs, every step slamming up through the column of her spine and rattling inside her head, she runs for the city's center.

Across the world, in Avengers Tower, a message blinks into existence on Clint Barton's computer screen. ULTRON. Latitude. Longitude.

"Is it Natasha?" Steve asks, sounding a little bit too concerned.

Clint shrugs. "I don't know. Could be a trap."

Almost like an afterthought, another message overtakes the computer screen: CLINT BARTON, I WILL KICK YOUR ASS FOR THIS.

"It's Natasha," Clint says, and sighs.

~x~X~x~

A/N: NATASHA FREAKING ROMANOFF, FOLKS. That is all.