Title: Slayer of Interest

Author: Jedi Buttercup

Rating: K+

Disclaimer: The words are mine; the worlds are not.

Summary: The Machine had kept giving Finch social security numbers from California. Week after week, the same little town. 1500 words.

Spoilers: Season 2-ish for Person of Interest; post-Chosen for Buffy.

Notes: For beckyh2112, for Day 9 in Wishlist 2012; the prompt is the summary. More or less. I had to tweak it a bit to fit the offical timelines.

In the early phases of the Machine, before Finch was ready to test it on current data, he'd calibrated it with examples from past records. Data gathered from before the modern, highly digitized age were often incomplete, but still of use in building predictive models, and by asking it to target specific moments he knew he could check the results against what had actually happened thereafter.

He hadn't restricted the output by geographical location, then, or by any differentiation in relevance. What had mattered was that it was correct, and that the results were verifiable.

The project had been productive enough to be of considerable use in shaping his algorithms. However-there had been a few anomalies in the data, ones Finch had never been able to explain. He'd told Reese, once, about the numbers he'd seen come up again and again before they worked together, and how he'd finally realized it meant the victims were living with the person who would eventually kill them. But he'd thought it a mistake at first- and part of the reason he'd thought it was a mistake was because of one of those peculiar inconsistencies in the past predictive data.

The Machine had kept giving him social security numbers from California. Week after week, the same little town. A constant background trickle of numbers from the earliest data to which it had access, accelerating into a veritable storm in 1997 or so, and continuing through to the town's eventual collapse in May of 2003. It had occurred to him to check whether or not the Machine might have somehow realized the collapse was coming, perhaps from seismic data, and had been flagging numbers by their likelihood to be near the epicenter when it eventually happened; but even that had not panned out. Surprisingly few residents had still been within the town limits when the sinkhole swallowed it whole.

Many of those numbers had been repetitions. And a very specific subset of those had shown up on an extremely regular basis, flagged at least once a week for the entire period between the upswing in activity and its unavoidable cessation. He'd never understood it; he had never seen another pattern like it anywhere else in the country. And curiously enough, though a high percentage of the repetitive numbers had in fact escaped Sunnydale alive, he had not seen any of them again, not then and not since he'd turned the Machine over to the NSA's care.

Not until that very morning, at least. Finch wrote the newest number on a slip of paper in a shaky hand, able to translate the code generated by the Irrelevant List without even bothering to look it up. It was the Most Frequent Number herself: one Buffy Summers.

She was there. She was still alive, and she was there.

Finch felt curiously lightheaded, staring at her social security ID written out in his hand. He could almost taste the ozone in the back of his throat from those long, frustrating days manipulating code; could almost feel the throttling despair of watching names like Jessica Arndt's come up again and again and wondering if this would be the time her abuser killed her. It felt like a second chance reclaimed- like the solution to an old mystery fluttering unexpectedly back into his grasp.

And, of course, a chance to save a life that had been- apparently- endangered so many times already, more than anyone should have to endure. Ms. Summers was barely thirty, even now! If he could only find out what had threatened her, whether it be some unrecognized environmental factor or extreme gang violence, it would increase their chances of saving someone in like circumstance in the future.

He was deep into refreshing himself on her life story by the time Mr. Reese arrived at the library with a cup of tea and a box of pastries, smiling faintly as he taped a picture of a dark-haired young woman to the pane of glass they used as a case board. Another Sunnydale survivor to check off against the list he'd never quite forgotten.

"Pretty girl, Finch," Reese said, looming up behind him to brush a finger against the photo. Then he touched the one next to it, of a slightly older blonde in casual businesswear with a no-nonsense hairstyle, and his amused expression faded into a light frown. "Her, too. Which one's our number?"

Finch gestured to the blonde, then at the legend above it. "Buffy Summers. An executive with an international organization based in Britain known as the ISWC; she travels extensively and just arrived in New York this morning. I did find a few less ambiguous, but no less inexplicable references to an International Slayers and Watchers Council; presumably, like KFC Corporation, the current company shed the original name but kept the acronym for recognition purposes."

Reese raised his eyebrows. "You mean it's not Kentucky Fried Chicken anymore?"

"Not since 1991, in fact, although the company still occasionally references the older name for advertising purposes," Finch informed him dryly. Then he continued. "The second young woman is Buffy's younger sister, and presumably the reason for her being in town: Dawn Summers is pursuing a graduate degree in linguistics at Columbia University."

"Huh. Sibling rivalry, maybe?" Reese mused, glancing between the photos again. "Anything going on in Dawn's life that her sister might have reason to be jealous of?"

Finch had been so accustomed to thinking of Buffy Summers as a recurrent victim that the suspicion in Reese's voice caught him entirely off guard. Dawn's number had appeared less frequently than her sister's in the Sunnydale Anomaly reports, and then only during the last three years of its existence. "You think the elder Ms. Summers is the perpetrator?"

Reese blinked at him, apparently equally surprised. "You don't?" he said, then gestured back to the board. "Look at her eyes, Finch; her stance. How recent is this picture?"

"A few months old, why?" he replied, studying the image with a furrowed brow. It looked no different to him than it had when he'd put it up, or than any of the other photos of her he'd seen, though of course she no longer wore revealing teenage fashions. But she'd always dressed as well as she could afford and carried herself with a certain strength that had caused him much confusion and concern. What was Reese seeing that he had not?

"She looks- familiar, somehow," Reese frowned. "But I think it's more her body language than anything specific to her. She's had training of some kind; I'm sure of it. And she's seen more than you'd expect in someone with her age and a corporate occupation. This ISWC aren't mercenaries, are they?"

"Not as far as I can tell. They read as a historical association primarily concerned with the acquisition, cataloguing, and translation of artefacts and documents of all types." Finch shrugged. "The younger Ms. Summers is also working there part time while she finishes her education."

"Any boyfriends or husbands in the picture?"

"One; Dawn is currently engaged to a young man who attended high school with her sister. However!" He raised a finger as Reese's expression lit with interest. "The engagement is one of many month's standing, and I can find no record that Mr. Harris was ever romantically linked with Buffy Summers in any way. That's not conclusive, I realize; but she would have had plenty of opportunities to act before if the relationship was objectionable to her."

He lifted another photo and taped it into place beside Dawn, then linked the two with a swipe of erasable red marker. He seemed a reasonably healthy, reasonably good looking individual; though he did have one... rather unfortunate feature.

Reese snorted at the image. "Maybe she did. When did he lose the eye?"

Finch shook his head. "In 2003. Just before their entire hometown fell into a sinkhole. All hospital records of the incident were lost, but a fragmentary police report remains, claiming that it was the work of a religiously-motivated serial killer named Caleb Pardy."

Reese grimaced. "So this isn't these girls' first brush with violence."

Finch swallowed at that. "Far from it, I'm afraid," he said, touching Buffy's image again. But he only shook his head when Reese threw him a glance for clarification.

"This is her sister's address," he said, gesturing to the number and street name written under her face. "She's staying there for the duration of her visit."

Reese glanced at the address indicated, then nodded. "I'll check it out. Let me know if you find anything else relevant."

"Of course," Finch agreed. Then he turned back to the computer and opened up a new window.

If the two of them are here, then where are the others? he asked himself. Are you one of the Slayers of the old title? Or does someone mean to slay you?

This time, he would not be satisfied with allowing his questions to go unanswered.