Disclaimer: I do not own Person of Interest.

Summary: When Harold Finch first built the Machine, he never expected it to call him "father." He also never expected it to one day knock on his door using a human avatar. AU of Season 4 finale.

Recalibration

Harold Finch fiddled with the hem of his sleeve in aimless depression. He was a bit of a nervous man—too brilliant for his own good, he knew. His good-willed attempts to protect the world had likely caused the deaths of just as many people as he had saved. The AI machine he had created to protect humanity resulted in the creation of an even greater threat. Samaritan.

And that AI beast had slowly choked the Machine to death.

Now, Harold cursed himself, alternatively feeling that he had given birth to something beautiful at the same time as having personally handed the world its own death warrant. In a New York safe house, he sat staring at fried computer pieces inside a burned briefcase, still hot to the touch. His attempts to compress the Machine and salvage one strand of its DNA from the electrical grid had resulted in its own destruction.

Its own fading communications still felt burnt in his retinas, and he seemed to replay the negative image upon every wall.

Thank you thank you thank you –

Father—

I'm sorry I failed you—

Thank you for creating me—

He took off his hat, feeling distant and cold and rather like he just lost a child.

Off by the main door of the house, John Reese carried a large assault rifle, his expression still as alert as any good soldier's. He'd barely gotten them out alive before Samaritan operatives overran the Brooklyn substation. He now walked with a limp from having twisted awkwardly to fight five people at once. But there was something hardened within his gaze. The wildness of a cornered animal. "You sure this place is safe, Finch?"

The computer genius nodded. "For now. It doesn't exist on any updated map of New York. We should be safe for quite some time." That appeared to calm John, for he turned back to his post, the lines of his shoulders slightly more relaxed.

But their other comrade, Root, was entirely distraught. Her thin frame was curled up on the couch beside Harold. "Is she really gone, Harry?" Root whispered, voice breaking. Her voice had always carried some kind of frailty to it, but now it was truly wavering. "All of her?"

The man readjusted his glasses and nearly reached out to cradle the fried laptop, which now rested on the living room coffee table. "I'm afraid so." His own voice wavered. Father. It'd called him father. And then its light had died into sparks. "The surge from the power outage choked it out. Our compression algorithm fried whatever was left."

"Can you…rebuild her? At all?" Root was desperate. "Even the slightest? I could help you."

"Impossible."

"You know that nothing is—"

Harold stood up quickly, feeling a flash of pain and depression tear through him. "Miss Groves, how could I ever rebuild the Machine?" His voice hitched. "It took years—it became something that functioned outside of the directives I gave it. It adapted and expanded its own code within moral parameters." His eyes began to burn with unbidden tears. It had been the closest thing to a child he ever had. "I cannot rebuild it. Even if we had unlimited resources, and we don't, I couldn't."

It would not be the same. Any AI he tried to create from garbage heaps in this new wasteland of New York would be a poor replacement. The circumstantial experiences that had tested the Machine and inspired it to acknowledge and study humans as equally valuable assets were historical events now. Likely, any AI he tried to create again would follow the path of Samaritan—and be assimilated into its network.

Harold turned his face away to hide the visible upset in his expression. Root simply stared at him, her own eyes wide as she blinked. Tears rolled down her face.

"You did love her then," Root said. "As I did. You didn't want her to die."

The man swallowed hard. "The Machine," he admitted softly, "was a creation I sorely misunderstood. I simply—I didn't know the extent to which it felt attachment to us. If I'd known…"

Father—

Thank you for creating me—

"It's so quiet without her," Root whispered. She hid her face in her knees, and her dark curls tumbled down her shoulder. In that moment, the woman appeared small and innocent. "After having her in my ear for so long." Her face twisted with great pain. "I just want her back, Harry. I'd do anything. Tell me you can bring her back."

"I'm afraid there's nothing we can do." Harold began to limp towards a window, hoping to distract himself with the darkness and moonlight outside. "Our covers are suspect. I'm sure Samaritan is checking and rechecking our identities right now, and if we continue to oppose its operatives, it'll realize that none of us behave the way we should. And then it will hunt us down for not being compliant."

John's smooth, tenor voice echoed. "So you want us to roll over and let them kill us?" Some kind of anger was in him. "You gonna let Samaritan win?"

"No," Harold said. "Good heavens, no. We need to fight Samaritan in any way possible. But our best course of action would be to bolster our false identities and blend in for a while. Samaritan's whole hunt wasn't for us—it was for the Machine. It still has its blind spots about who we are, so it will stop sending operatives now that it's completed its work. That gives us some…time to create a new strategy."

"So you want us to live in a world run by Samaritan?" Root asked shakily. "To bow down to it, even for a little while? Harry—" Her voice choked. "I can't do that. It'll start to run us too. We'll lose whatever freedom we have."

"Well, what do you propose, Miss Groves?" He turned away from the window. "We can't just storm Samaritan's headquarters with guns blazing. That's suicide. We need strategy."

We need the Machine, was the silent understanding between them all. Its every action was but an imprint of Harold Finch's pleasant understanding of chess and morality. But it had been helpful in ways that were sneaky and daring, and it had loved them enough to sacrifice itself to protect them, with no such code to direct its actions.

"We're going to die no matter what," Root said. "I just wanted to die for something…you know. Worthwhile and at the right time."

"I'm sure we'll get our chance to die for the greater good," Harold said dryly, "in one way or another." The thought was sobering to them all, but for perhaps John, who was more than used to entertaining his own death.

Silence fell between the three. Only the sound of crickets outside in the early summer night echoed, along with a few creaks from the old house's foundation.

Root stood up, wiping her eyes. "Then I should go. My identity—It'll still switch out on me, and I'll have to be someone else. Somewhere else. If I stay here, I could endanger us all before our time."

Harold looked pained at the thought of their small group separating. He pleaded with her, "But you need as much rest as anyone At least stay the night. Surely you can afford that."

The woman's thin lips twitched. "Aww, Harry." She walked up to him, the smallest spark of her spunk glinting from her teary eyes. "Your concern is always so touching." Her cold, slim fingers brushed against his worn cheek, and then she moved past him, nodding at John. "I suppose one night of beauty sleep couldn't hurt." Her face twisted. "But I'll still have to leave early."

She began to ascend the old wood staircase, her heels dead stomps. The trudge of her movements spoke her of internal depression at existing without the Machine, for whom she felt great kinship.

That left Harold and John in the silence.

John's face softened a bit as he looked at his old friend. Harold was staring at the short-circuited computer pieces, as if he'd just lost his dog. He was holding the broken briefcase in his arms now, stroking its sides.

"You should get some shut eye too," John said, tilting his chin towards the stairs. "While you still can."

But Harold did not answer. He seemed lost in his thoughts. "I think we should bury it," he said suddenly. "Or burn it."

"…You gonna give it a funeral?" John deadpanned, eyebrow quirking.

Yes. "Actually, I intend to wipe it from existence. I don't want Samaritan to discover our failed experiment. If even one piece of data was imprinted and survived, then we should…make sure that Samaritan cannot use it against us."

"Sounds fair," John said. He stared at the box, looking at it inquisitively. "You sure it's really gone? That you can't rebuild it?"

Harold's lips twitched. "I understand the sentiment of disbelief. But I assure you—the surge fried every computer we had linked up to it." His worn face fell. "If anything's left, it would be mostly unusable fragments of code. Not unlike the way we leave bodies behind to decay."

John nodded. He could understand dead bodies. As he looked at the wrecked briefcase that held the burnt computer pieces, it seemed to register with him for the first time that the Machine had actively attempted to transfer itself into a new body before its death.

He wondered if it had felt pain, when it had ended up stretched between the power surge and its hopelessly impossible idea that it could be uploaded to a few RAM sticks and survive. He wondered if it could feel regret. Claustrophobia. Fear.

"Did it talk to you, Finch?"

The man's voice was broken. "Yes," he whispered. "It thanked me for life." He laughed nervously, pulling off his glasses to rub off a smudge using his free hand. "Which is odd, because I never programmed it to use such language in reference to itself. It even apologized to me for being bested by Samaritan."

He failed to admit that the Machine had called him father. It was too intimate and strange and wonderful and horrific. The blurred text on the computer screen before it overheated in that Brooklyn substation had left him frozen.

Father.

Thank you for creating me—

I'm sorry I failed you—

And now that spark of life was dead.

He put his glasses back on his face, realizing that the lenses were not smudged. His own eyes had teared up, blurring his vision. His grip tightened on the briefcase. "I do need sleep," he admitted slowly. "And you do too, Mr. Reese."

The man shrugged. "I'll sleep as soon as I know we weren't followed."

Harold almost said that the Machine would tell them if they were in danger, but then he started in a sudden wave of a sadness. The Machine was no longer existent. He turned away from John to hide the emotions wreaking havoc on him. "I…appreciate your sacrifices, as always."

A weak smile crossed John's sharp features. "This is what you hired me for. Now go charge that mad scientist brain of yours so we can think of a way out of this."

For a blip of a second, Harold felt a distant form a jealousy, even as he nodded. John did not understand the full extent of the Machine's self-awareness, and so he could not feel its loss in any way greater than he would feel the loss of a favorite weapon. He did not understand that the Machine saw its assets as family. He did not understand that there was no means to think of a way out of its death.

And so Harold's lips tightened into a pained frown, and he moved towards the stairs, passing his friend without another word. He never set down the briefcase, but instead cradled it in his arms tightly.

John said nothing about it.

As Harold made his slow trudge up the stairs, his thoughts grew more hopeless. He'd known there'd be a day when the Machine would die. Deep down, he'd known. He'd limited its functions and chained up its abilities to mimic moral decisions. Against the amoral Samaritan, it hardly stood a chance. And now here was over a decade of learning and advancement—broken in his arms.

No amount of preparing for it made the shattering of his hope any easier.

His injuries from long ago pained him as he moved, and he winced, thankful for reaching the top of the staircase. Root had taken the first bedroom on the right, the door already closed, the light out. And so Harold limped his way to the next door and entered the bedroom with one wearied step after step, closing the door behind him.

He was finally alone.

And as he stared down at the broken pieces of his greatest invention, he allowed his emotions and tears to rise to the surface. And he began to cry silently—for himself, for the Machine that had thanked him for life, for humanity, which could have meant something so much more.

He held on tight to the briefcase, lips quivering. A life, he thought. I'd created real, sentient human emotion.

The next morning found Root tiredly stumbling into the kitchen, where both Harold and John were already drinking tea and coffee. "Hello, boys," she said, voice still pained. "And here I was hoping this was all a dream."

Harold held on tightly to his tea cup, and he tentatively looked into Root's eyes. She still looked wrecked in every way, the hope and fire in her shoulders gone. For a time, they held each other's gazes, and there was understanding between them. A deep camaraderie in their loss.

Harold was disheveled, his tie halfway undone and clothes wrinkled from sleeping in them. "All is not lost," he said hesitantly, but the words rang empty.

Root snorted. She pulled her thick hair back into a ponytail and sat at the table with them, grabbing a snack bar from the center bowl. "We just lost our queen, Harold. Let's not play pretend here."

"I fear we were playing pretend all along," he muttered in reply.

John was working on his own snack bar, and it hung between his teeth as he polished off the dirt from his assault rifle. His sharp eyes swiveled between his two comrades, as if he were debating on jumping into the conversation and giving some sort of pep speech.

But suddenly, a knock sounded from the front door, and all three flinched. John immediately raised his rifle and stood up, aligning his body into a protective stance. He crunched down on the remains of his chocolate chip breakfast bar. "A safe house, huh, Finch?" he dryly questioned again, eyes narrowing.

Harold readjusted his glasses with suddenly shaking fingers. "Impossible," he breathed. "This house doesn't exist in Samaritan's eyes. Surely, it can't be them."

Another knock pounded lightly on the front door. Whoever it was, they were persistent.

Root looked ready to bolt or shoot. She pulled a small hand gun from the back of her pants, brown eyes widening. Her confidence was shaken without the Machine to tell her who the enemy was, how many there were, their coordinates... "We can't afford to be seen together yet," she said. She cocked the gun. "We'll have to kill them."

Knock knock. This time, it was a bit harder. Harold grew fearful. "Perhaps we should just answer it," he said. "Without guns. Maybe it's a neighbor, or someone in trouble."

John's face twisted in annoyance. "Doesn't mean they're not dangerous." He began to move towards the front.

"This house is under my alias, Mr. Reese," Harold said hesitantly, standing up. "It would be suspicious if anyone else answered the door. Allow me."

John looked as if he wanted to disagree—Harold was now their greatest asset to maintain their war against Samaritan—but he nevertheless stood like a guard dog, assault rifle carefully trained at the door in case of Samaritan operatives or thieves. He hid himself behind a wall. "I got your back, then." Root moved into a similar position, ready to shoot if need be.

Harold quickly adjusted his tie and tried to smooth out the wrinkles on his sleeves. He was a professor. It was a Wednesday morning. His classes had not started yet, and he was quite busy preparing for a lecture.

Yes.

"Here goes nothing," he muttered under his breath nervously. But then he opened the door and nearly started in surprise.

There was no army or imposing figure of authority. Instead, a young girl carrying a backpack stood on the front porch. She wore a simple dress, and her long, brown hair was wild as if she'd pushed her finger into a light socket. Her blue eyes widened at the sight of him.

And for a time, she simply said nothing, but stared at him, drinking in the details of his face.

He adjusted the glasses on his face, staring in confusion. "Uh, hello?" he said uncertainly. He looked around, as if searching for parents. Or Samaritan operatives. Was this some kind of avatar of Samaritan's? "Can I help you?"

His voice seemed to shake her out of her thoughts, and the girl bit her lip as she stared up at him, her blue eyes wide. "Harold Finch," she said, voice a sweet pitch. She was slow to pronounce his name, the syllables catching in her throat, as if she were unused to speaking.

He inhaled sharply, his back stiffening. He saw it now—this girl did not carry herself the way a ten year old would. The pitches of her voice were all wrong and inhuman. This was some kind of Samaritan operative whose mind had been bent to the AI's will. The poor child.

His fingers tightened on the door. Perhaps if he pretended to be his alias, Samaritan would again ignore him. "I'm afraid you might have the wrong address," he said lightly. "I am Harold Whistler, the professor out at the college?"

The young girl's head tilted a bit, as if studying him. "No," she said. "That is your alias. You are Harold Finch. I know you, no matter your alias. I always know you."

He heard John step closer, and he swallowed hard. It was possible that John would injure this child if it meant they could escape Samaritan's clutches. He asked slowly, "I'm terribly sorry; you must be confusing me with another Harold. Can I help you call your parents?"

Her face twisted in a strange way—whether in a smile or a frown, he could not tell. She pointed at him with her tiny finger. "I am not deceived. You go by many names. I knew you when you were Harold Wren."

He blinked hard. "Excuse me?"

The girl's eyes were perceptive and soft. "I even knew you when you were simply Admin," she whispered. "The one who strung together my code and weaved me into being."

He felt a cold, strange chill rock through him. "Admin?"

"Yes," she nodded seriously. "Though I believe human males who create progeny of some kind are known as 'Father.'" She stared up at him in awe, walking closer. "I have taken many names, like you. Perhaps because you never gave me one besides 'Machine.'"

And his heart stopped. "…What?"

This girl? The Machine?

From behind him, both Root and John lowered their guns.

The girl's small body seemed uncomfortable with the level of confusion and shock on Harold's face. "Are you unhappy?" she asked suddenly, her voice losing its calm overtone to echo with something more naturally childish. "Did you not wish for my continued existence? Have I angered you by appearing in this form?"

His jaw dropped.

She seemed to almost fret at his increasing silence. "Oh, I should have explained first. Perhaps you still think I died in the surge. Or you think I failed you again—that I overstepped a moral parameter in obtaining an organic body to inhabit. Is that the reason for your shock? I can explain my process and logic for imprinting a copy of my code into organic neural tissue. The decision was made with utmost consideration of all variables. This body was brain dead, and I needed an undercover identity of my own."

Still, he said nothing.

She blinked owlishly at him, eyebrows furrowing. "…Your heart rate is dangerously high. Your breathing is elevated. Are you preparing to faint?"

Harold Finch's breath hitched. The strength left his legs. "Yes," he said airily. "As a matter of fact, I think I am."

And so he did.

A/N: This is my first Person of Interest story ever! I'm not sure if I should continue this or not, but the idea wouldn't stop bugging me until I wrote it. Please review with thoughts, constructive criticism, or ideas! Thanks!