Variable Onset

by Layla Reyne

  “Ollie, you’re too close—”

  “L, you called me, not Beverley, which protocol dictates, by the way, because other than you, I am the other best person to work this case. And fuck knows, I need something to do besides worry.”

  He was right; it hadn’t even crossed Lincoln’s mind to call Beverley. He’d face-palm if he could actually feel where his frozen forehead was; he’d rather not give himself a bloody nose, literally or metaphorically. “Okay, you pick up the victims’ thread there, and we’ll home in on suspects here. See who each of the first victims crossed paths with at the hospital and in Apex.”

  “I’ll update Bev,” Oliver said. “Good work, agents. Keep us posted.”

  Call ended, Lincoln lowered the phone, then lifted his gaze to Carter’s. Credit was due. “You may have cracked this case.”

  “I had a good teacher.” He smiled, the soft genuine grin that made Lincoln’s skin heat for entirely different reasons. “Even if he can’t remember to wear a coat in winter.”

  Fuck, Lincoln bet that’s what Jeremiah was going to say before he’d ducked out. Probably also why those passersby had looked at him like he’d lost his mind, on top of almost falling down the stairs.

  “I didn’t think—” Lincoln’s words died as Carter settled his jacket over his shoulders, heat of a different sort enveloping him. Leather, coffee...and fresh biscuits tickled Lincoln’s nose. “Thank you.”

  Carter’s hands lingered on the collar, pulling the flaps of the jacket tight around Lincoln, and damn if Lincoln didn’t wish for Carter to pull a different direction. Closer, toward him. The slightest tug and Lincoln would go tumbling, despite his better judgment. But right then, high on the victory of the first lead on the Dr. Fear case in years, he felt like diving. Deeper into those green eyes, into the dark curls the V-neck of his blue Henley teased at, into the heat everything about Carter Warren promised.

  Carter pulled away instead, clearing his throat and standing. “We should get inside where it’s warm and see what else we can find.” He held his hand out to Lincoln, the silver band catching the afternoon sun. A miniature flame where seconds ago there had been a raging fire, one Lincoln had both feared and considered walking into. That was a first. As was Carter’s restraint. It surprised Lincoln more than he expected. Impressed him too.

  He slid his hand into Carter’s. It wasn’t the heat he’d wanted but he’d take it. “Let’s go.”

  Chapter Seven

  Carter’s phone vibrated on the table, a new email notification lighting up the screen. He silenced the device and glanced up. If Lincoln had noticed, he didn’t acknowledge the disturbance, still speeding through slides on the reader.

  Still wearing Carter’s jacket. And glasses now too, which only made him more sexy.

  Smiling, Carter tapped at his phone screen, entering the passcode to access his personal email. His smile died at seeing the new email there. No luck, his contact at the state police reported. He thought back to what Larry had said this morning. About the family who’d died in a hit-and-run on the highway one bright summer afternoon three decades ago. He glanced again at Lincoln. If there was anyone who could help him... Or Lincoln might make a case example out of him. Or pity him. Or brush him off altogether. Carter didn’t think he could handle any of those outcomes, especially the last. He’d been brushed off enough times in life. He didn’t want to be brushed off by the guy he’d crushed on for eight years. And what would it say about Carter’s ability to contribute to their current case if he couldn’t solve the one that had stymied him the longest?

  There was a knock against the workroom door, and the grad student Carter had met yesterday poked his head into the room. “I’m headed out.” He tilted his head, brow furrowed. “Hmm. I thought it would be more of a wreck in here than this.”

  Lincoln rotated in his chair toward Jeremiah. “Oh, it was.”

  “Hey!” Carter balled up a piece of scratch paper and threw it at him. “I was trying to help.”

  Lincoln snatched the paper out of the air. “You helped by replacing those biscuits, which reminds me, we need to go back by—”

  “No.” Carter stood and strode to the end of the table nearest Lincoln. “You cannot eat at Flour Power three times a day.”

  “Personally, I beg to differ,” Jeremiah interrupted, and they both swung their gazes to their forgotten audience, who was rocking back on his heels, thumbs hooked in his suspenders. “Been going to FP all my life, and three times a day is not unheard of, but you two can argue out your own boundaries. I’m going to see myself out of this domestic.”

  Chalk it up to selling the cover, which Carter was about to possibly undercut with his next move, but he needed proof to back up a theory he was noodling, one that had niggled at the back of his mind since the police station and had grown louder at Jeremiah’s “all my life” remark. He crossed the room to Jeremiah and laid his right hand on Jeremiah’s shoulder. “Thanks for helping L get set up today.”

  “Sure thing.” Jeremiah smiled and dipped his chin, long lashes fluttering. Distracted just long enough for Carter to get what he needed. And thankfully before Lincoln, behind them, cleared his throat. Carter fought not to smile at what that grunt might mean. For his part, Jeremiah dropped the coy act and stepped out from under Carter’s hand. “I won’t be in tomorrow. Last day off before students are officially back. You two should get out of here too. Take some time around town before it gets flooded with students. Visit FP once more while you can still get a table.”

  “Don’t encourage him,” Carter said.

  A ball of paper hit the back of his head.

  Jeremiah laughed all the way out of the archives room and down the hall to the elevator, the sound fading as the mechanical doors whooshed shut. Carter had waited to be sure.

  “His ass is long since gone,” Lincoln sniped behind him. “You can stop staring after him now.”

  Definitely jealous, and Carter didn’t bother to hide his smile as he sauntered back across the room to where Lincoln now stood. “Not his ass I was interested in.” He flicked at one of the curls tickling his own forehead.

  Lincoln cocked a brow. “Baby silver fox fantasies?”

  His brow inched higher as Carter continued to draw closer, only stopping when there was less than a foot left between them. “I prefer actual silver foxes.” He lifted his left hand and wove his fingers through the ends of Lincoln’s hair.

  Lincoln’s breath hitched, and his gaze dropped to Carter’s mouth. Fuck, Carter loathed interrupting this moment, where he was sure it was headed, same as he’d loathed interrupting the one outside, but it wasn’t only his conscience holding him back this time. It was the matter of the hair in his closed right fist, and the one he needed to grab with the left. He closed his thumb and index finger around a silver strand and yanked.

  Lincoln howled and staggered backward. “What the fuck was that?”

  “Get the evidence bags out of my coat pocket.”

  “Evidence bags?”

  “Yes, I always keep a few in the inner pocket.”

  “For what?” Lincoln asked, as he dug out the plastic bags.

  Carter held his two fists out in front of him and turned them over. He opened the left one, cupped. “Your gray hair is a control.” Then he did the same with the right one. “Jeremiah’s gray hair is the variable.”

  “What are you thinking?” Lincoln opened one then the other bag for Carter to drop each hair into.

  “Dr. Fear leaves no evidence, right? So, per your lessons, we have to use archival data and documents, our own observational skills, and the one clue we do have, to identify likely avenues of investigation. All we know at this point is that they’re likely someone who lived or worked in Apex through the span of Dr. Fear’s cycles.”

  “Which, one, is too big a suspect pool, and two, Jeremiah’s too young.”

 
“But maybe not someone from his family. He tell you he was from here?”

  Lincoln nodded. “Family goes multiple generations back.”

  “Right, so normally it’d be tough to test for genetic relevance in a college town, as a large segment of the population is always turning over due to the university, but the size of the actual permanent population in Apex is relatively small and, from what I gathered talking to folks last night and today, much of it is like Jeremiah’s family. They’ve been here for generations, and many of them have intermarried.”

  Lincoln was nodding enthusiastically now. “Multi-generational founding families. That’s a much more manageable suspect pool and someone from one of those families is more likely to be stationary, here in Apex for the span of Dr. Fear’s cycles.” His brow furrowed and he drummed his fingers on the table. “Of course, there’s the possibility it’s someone on staff at Apex who has been here the entire time.”

  “Granted,” Carter conceded. “We need to follow that lead as well. Dig deeper into the university records. But for this investigative avenue, if we assume Dr. Fear does belong to a founding family, who has been in this isolated area for multiple generations...” He held up the evidence bags, Jeremiah’s a little higher.

  “Those families will have higher incidences of genetic mutations and other hereditary conditions. A founder variant.”

  “A variant like premature graying, which would narrow the suspect pool even more. You were probably too nervous to notice, but at the party last night and the café this morning, there were multiple other baby silver foxes. Plus Jeremiah and Lydia—she can’t be that much older than me—and probably more in their families.”

  Lincoln rested back against the end of the table. “That’s a relatively high incidence rate of premature graying in a town this size.”

  “Not to mention all the other gray hairs we don’t have data on—Barry, Larry, probably also your predecessor, Harry. I saw a bunch of pictures of them at the police station. They were all gray by thirty.”

  Lincoln held up his hands, fingers spread. “Wait, slow down, who’s Larry?”

  “Barry’s younger brother, the current police chief.” Carter rolled up each of the bags. “A quick Google search told me that premature graying is often connected with thyroid conditions or autoimmune diseases.”

  “Which can be a genetic founder variant in a population this size. If there are other, more serious mutations, that could help us narrow the suspect pool further.”

  “That’s where you and all the fancy lab equipment come in.” He handed the bags to Lincoln. “I’ve officially reached the limit of my genetics and genealogy know-how.”

  Lincoln pushed off the table, drawing closer to him this time. “That limit is higher than what I taught you, Agent Warren. This is more than a passing interest.”

  “I’m an investigator. Nothing more to it.”

  Honey-colored eyes cut to the single messy pile of papers left on Carter’s table. Carter shifted, cutting off his view. “Test the hairs, L. I’m going to stay here and do some research on the founding families and on longtime university staff. See if anything else jumps out.”

  Lincoln grumbled a protest but began packing his bag. “We’re coming back to this,” he said, halfway to the door.

  “I’m sure, Professor. Now go.”

  And he did, still wearing Carter’s coat.

  Carter’s smile hardly wavered as he bypassed the messy stack on his way to grabbing another box of archives.

  * * *

  Lincoln scrolled through the data the sequencer was feeding to his computer. It was a limited screen—it would take too long to fully sequence his and Jeremiah’s DNA—so he’d set it to search for certain markers, based on his and Carter’s earlier speculation. And it’d found one. “Bingo!”

  “What’ve you got?”

  Lincoln almost fell off his stool, limbs flailing in surprise. Once he had them, and his balance back under control, he glared at his partner in the doorway. “Are you secretly a ninja?”

  Carter chuckled. “No, just a well-trained soldier who excelled at stealth approach.”

  Lincoln was going to make a snide remark about the impossibility of someone who was so loud in his class being so quiet, but then Carter tossed Lincoln’s too-small-for-him coat on the back of the empty desk chair and snagged his own off the one Lincoln had dropped his bag into. “Shit, I’m sorry,” he said instead. “I totally walked out in your coat.”

  “It’s fine,” Carter said with a smirk. He claimed the bench stool next to Lincoln. “Unless you want to heat me up, Professor.”

  He stifled the “yes” that wanted to escape with snark instead. “I will heat you up with data.”

  Carter propped a foot on the bar of Lincoln’s stool and leaned in. “Oh, baby, talk dirty to me.”

  Lincoln covered his face with his hands and laughed. No other choice, and Carter laughed with him, warm and bright, and it was a welcome respite after hours of grinding work. Smiling, he peeked out from behind his fingers at Carter. “Thank you.”

  He returned the grin. “You’re welcome. Now, show me what you got.”

  “You were right that Jeremiah’s gray hair is a genetic variant versus mine, which is a result of old age.”

  “Seasoned, L. The word is seasoned.”

  “Yes, well, Jeremiah has not seen as many seasons as me. Though I’d bet he’s seen more hospitals.” He tapped at a genetic marker on the screen. “This is a frameshift mutation that is associated with increased susceptibility to Crohn’s disease, which in this case may also be a founder variant.”

  “English, Professor.”

  “You were doing so well with the science-speak before.”

  Carter held a hand up, at about the level of Lincoln’s chin. “Limits, remember.”

  Lincoln chuckled, lowering Carter’s hand, his own lingering on his longer than strictly necessary before he withdrew it. “A founder variation, or the founder effect, occurs when a small population separates from a larger population, thereby cutting off the gene pool. So if there are any anomalies in that gene pool—”

  “They’re likely to get replicated.”

  “Exactly. Take the higher incidence of Huntington’s disease among Dutch Afrikaners, fumarase deficiency in LDS members, or polydactylism in Amish populations. Segmented populations, by geography, religion, or choice, where gene pools are limited and anomalies replicated.”

  “Which in the original Apex population may be premature gray hair and Crohn’s disease?”

  “Premature gray hair is the thing we can visibly see. Jeremiah also having Crohn’s may just be a coincidence, but autoimmune conditions, such as Crohn’s, have been linked to premature graying.”

  “What about the frameshift thing you mentioned?”

  “Right, so DNA base pairs come in sets of three. A frameshift variation occurs when a base pair is deleted or inserted, and it is not in a set of three, so it causes a disruption in the chain. Increased susceptibility to Crohn’s can arise from, among other things, a frameshift variation.”

  “And if that frameshift variant existed in an isolated population?”

  “It could also be replicated, passed down, and characterized as a founder variant.”

  “We need to call this in,” Carter said, already pulling out his phone.

  Lincoln laid a hand over his, stilling it before Carter could call Beverley. “Like I said, the Crohn’s disease could just be a coincidence.”

  “But not the premature graying. That seems statistically relevant, yes?”

  Lincoln nodded.

  “Good. All that work I just put in at the library won’t go to waste.”

  “What’d you do?”

  Carter swiped Beverley’s contact away and opened his photos, then held the phone so Lincoln could see. “Using the time windows establ
ished for Dr. Fear’s earliest cycles, I started going through photos, particularly town events, where so-called founding families would most likely be, and I flagged those with baby silver foxes.”

  Lincoln flipped through the pictures, most of them in color, making the young silver-haired persons stand out even more. He paused on one, a shot at a ribbon cutting. He spread his fingers to zoom in on the uniformed officer. “Is that Barry?”

  “Maybe, or it could be their father, or Harry or Larry. They all looked similar in the photos I saw at the station. I can’t be sure without asking them or doing more research to conclusively ID everyone in the photo.”

  “Asking them will blow our cover, and if the police are involved...”

  Carter nodded. “We can’t blow our cover.”

  “You’re right, though.” Lincoln closed the photo app and handed the phone back to Carter. “We can call this much in. Let’s get forensics to double check evidence from the past scenes. Hair samples especially. At least two of Dr. Fear’s victims were older and had gray hair. Let’s confirm any gray hairs collected at the scene were theirs. If there were gray hairs found at the scene that aren’t theirs, then maybe those belong to Dr. Fear. And if none from past scenes are found, let’s see if any were or can be found from the scene where Ruby and Chase were taken. Neither of them has gray hair.”

  Carter hesitated before clicking on Beverley’s contact.

  “What is it?” Lincoln asked.

  “The premature graying... Are we attributing that to Dr. Fear or the copycat, or both?”

  Good point. In his excitement at catching a break, Lincoln hadn’t made the distinction. Then again, the copycat wouldn’t want to either. “I think we use it to potentially narrow the suspect pool for Dr. Fear, and going on what you said earlier, let’s assume that a copycat would either find the premature gray a commonality with his idol or he would want to emulate his idol.”

  “So we have forensics also check for gray hair dye?”

  “I think so.” This time Lincoln forestalled the call to Beverley, a hand on Carter’s knee. “This may be nothing,” he said, reining in their shared enthusiasm. “The gray hair connection is just a theory. A place for us to start. But a long-term Apex U employee, gray hair or not, could be just as likely.”