“The equations are extremely high-level,” Zoe said, feeling a little like a failure for even admitting they were too much for her. Still, it had to be done. Eyeing the neat ninety-degree angles of everything arranged on Maitland’s desk, instead of watching his expression, she pushed herself onward. “I believe we would do better if we brought in a subject matter expert. Someone who could work on the equations from a professional mathematics standpoint.”
Maitland nodded, then paused in his writing as he realized that she was done. “Do you have someone in mind? Special Agent Rose reminded us that you studied math once upon a time.”
“I do, sir.”
“Good.” Maitland’s attention returned to the paperwork, effectively dismissing her. “Permission granted. Have the paperwork turned in ASAP.”
“Yes, sir.” Zoe turned and almost fled for the door, happy to have such a positive outcome. She was not going to stick around and wait for him to change his mind, by any stretch of the imagination.
There was work to do—and someone very important to bring into the case.
Zoe waited expectantly, watching her mentor examine the images.
“These are… disturbing.” Dr. Applewhite shook her head, holding her lower lip between her teeth for three seconds as she slipped the photograph to the back of the pile in her hands and studied the next one. “I sometimes forget that you have to look at this kind of thing day in and day out. It must take a toll.”
Zoe shrugged. “Dead bodies are dead. It is the not solving them that bothers me.”
“And this is one that you haven’t yet been able to solve.” It was not a question. Zoe had already primed the doctor with the fact that she needed help. Dr. Applewhite knew that it was an open, ongoing case, and that permission had had to be sought for them to even be having this conversation. She understood also that time was of the essence. With every passing hour, it became less and less likely that they would find the person who did this.
The thing about homicides was that the first twenty-four hours were crucial. Everyone knew that. Forty-eight hours without an arrest, and you were starting to head into dangerous territory. The kind of cases that would become episodes of late-night TV shows.
The college kid had been dead for well over forty-eight hours.
“I need to know what it means,” Zoe explained. “Right now, this is the only lead that we have. There does not seem to be any connection between the professor and the student, beyond the fact of their locations. No witnesses, no coverage of surveillance cameras. We have to figure out what kind of message the killer is trying to send if we are going to stop him.”
Dr. Applewhite was frowning down at the images, and she placed them beside Zoe’s notes to run through the calculations Zoe had already made.
“Your working seems sound,” she said, after a while had passed. “I can’t see anywhere else to take it that you haven’t already gone. This is extremely advanced—beyond even the level that I work at.”
Zoe’s heart sunk in her chest. She had been sure, so sure, that Dr. Applewhite would have the answers. Now, it seemed, those hopes were dashed.
She was already thinking through alternatives, trying to figure out what she was going to say to Shelley, when Dr. Applewhite spoke up again.
“I know some people who might be able to help,” she said. “Professors. A couple of mathematicians who work in other fields. If I can show this to them, I might be able to get a bit further with it. This is the kind of challenge that they will all love, so at least we’re bound to get some skilled hands on deck.”
Zoe nodded her approval. “That would be helpful.”
Dr. Applewhite tucked her graying bob behind one ear and looked up, fixing Zoe with that same curious stare now. “How are you holding up on this one? It’s not often a math question comes up that has you stumped.”
Zoe considered lying for a brief moment, but then let her shoulders slump. “A little like a failure. This is my specialty. I should at least be able to work it out. If I cannot, who in the FBI is going to?”
In anyone else’s voice, it would have sounded like a brag. To Zoe, it was pure fact. Analysts and their like might spend all day working with numbers, but they didn’t have the instinctive grasp on them that she did. They couldn’t look at an equation on the page and see the answer as clearly as if it was written out beside it. At least, that was the case for her usually.
This one was something else.
“You can’t be expected to solve everything. No FBI agent in the history of the Bureau ever had a one hundred percent solve rate.”
Zoe smiled a wan smile. “I am sure that there have been examples. Agents who were killed or retired just after solving their first case, for example.”
Dr. Applewhite rolled her eyes. “Trust you to find the loophole. All right, I will make some calls and get these equations out in front of some of my colleagues. I won’t tell them what it’s for—just that it’s urgent and a big challenge. That should intrigue them enough to get them working on it. I will let you know the moment anyone makes a breakthrough.”
“Or anything else, too,” Zoe prompted. “If someone finds a mistake, or a sign that something is missing. We were not able to fully check the first body to see if anything was missed by the photographer. Bear in mind that we also do not know whether this is intended to be one equation or two separate problems.”
“Understood.” Dr. Applewhite placed the photographs down on the desk in front of her, two inches off to the right, closer to her laptop. A gesture that reassured Zoe of her intention to begin work as soon as she had the chance. “Now, what about Dr. Monk’s recommendations? Have you thought anymore about—”
Zoe’s ringtone blasted out from her pocket, accompanied by strong buzzing. Saved by the bell, she thought, as she made an apologetic face and answered the call.
“Special Agent Prime.”
“Z, it’s me. I got a hit in the professor’s emails.”
“I am on my way,” Zoe told her, ending the call and jumping out of her seat with a nod to her mentor. Whatever it was, it had to be more promising than the nothing that they had.
CHAPTER SEVEN
Zoe pulled the car into the campus parking lot. At this time of night, the evening drawing down rapidly, it was fairly full—the cars belonging to students who lived in the various dorms and apartments scattered around. Each of them bore a university permit stuck to their front windshield. Zoe’s car had something better—an FBI sticker.
“Read it to me again?” Zoe asked. She was still unsure about Shelley’s theory. Being angry about a dropped grade was one thing, but angry enough to kill?
Shelley brought up the email on her phone without even a sigh of frustration, to her credit. She had saved the screenshot and brought it along as proof—proof they would need if they were going to confront the student who had sent it.
“‘Professor,’” she read. “‘I can’t believe you flunked me. Like, are you serious? I tried really goddamn hard on his paper and you just decided to kick me off the course! Teachers are supposed to help and support. Thanks a whole fucking bunch. You’re the worst professor I ever had. I hope you get fired. I’m not the only one who hates your guts. You’re going to get hauled over the coals if the dean listens to our complaints. Try sleeping well tonight, asshole.’”
Zoe had already zoned out by the time Shelley was done. She had heard it a couple of times before, and this time had not changed her opinion. It was student bluster, that was all. Threats made to his career, not to his life.
Not to mention that the student in question was studying English, not math. It was not a close enough connection. How could this barely literate student have known to write out complex equations? Complex