“He’d have to be AB-positive, then,” Dixon remarks. “Or he’d be in a world of hurt.”

“AB-positive is the universal receiver, is that right?” Cooper asks.

“Right. Otherwise you’re looking at hemolytic transfusion reaction, cascade clotting—”

“He might know that. He always took blood from the left arm.” Cooper looks at Emma.

“Is that important?” she asks.

“The heart skews to the left, and the ventricles point left,” Westfall says. “It’s generally the preferred arm for blood samples.” He peers at Cooper. “You’re thinking medical training?”

“Maybe, yeah.” Cooper has a light in his eyes. “Access to ether, the abrasions to hide a needle mark, the left arms, a possible transfusion…”

“Jesus.” Somewhere in another office, a phone rings. Westfall ignores it. “It would actually work well with the analysis of the throat wounds—no hesitation marks, fine sharp blade. This guy is very efficient at cutting a jugular.”

Emma turns to Bell, vibrating a little with the energy of the dots connecting in her head. “Someone they think they can trust.”

His eyebrows bunch. “A doctor?”

“That seems unlikely, given we’re looking for a college-aged suspect,” Cooper says.

Emma nods. “I get that, and it’s rare—but possible. Especially if he was accelerated in high school. It would explain his control, and the idea of a grudge—a smart teenager, maybe socially isolated.…”

“Or he could be passing himself off as a doctor,” Westfall suggests. “It’s been done before.”

The phone is still ringing. Dixon looks around. “Anyone gonna get that?”

“I’ll take it.” Neilsen drags himself away to the door.

“Or he could be a medical intern.” Emma throws out more ideas. “An ambulance assistant, a trainee nurse, an army medic—”

Cooper has pulled out a notebook. He checks his watch. “Gerry, it’s going on six thirty—we need to call the ME in Harrisburg at home. Don’t let them release Barnes’s body until we’ve confirmed. And tell them we want closer shots of the elbow joints, the… What did Glenn call it? The cubital fossa. We want shots of Ramirez, too.”

“You thinking of exhuming the other two bodies?” Westfall asks.

“Maybe. Give me the department numbers for county health?”

Dixon smiles broadly at Emma. “You did good.” He turns to Bell and speaks in Spanish. Bell coughs a little, replies, and they both chuckle.

Emma frowns at Bell. “What did you say?”

“I just told him you were too smart for him,” Dixon says with a smile.

Bell’s cheeks flush, but he’s grinning. “And I said he’s got it wrong—that I’m the brains, and you’re the muscle.”

Emma snorts, looks left as Neilsen rushes back into the doorway.

“Ed.” Neilsen’s face is chalky. “That was Gerry’s line. Police in Clarke County just called it in. They’ve found another crime scene in Berryville.”

CHAPTER NINETEEN

Cooper is on the phone in Neilsen’s office, using a voice of command that Emma hasn’t heard from him before.

“… until I arrive. Yes, the entire area. Tell Clarke County PD if anyone enters the building—I mean anyone—I will make it my personal mission to get them demoted to parking inspector for the rest of their career. No one touches anything until I get there with the team.… Yes, Gerry Westfall is coming, I’ll get him in the chopper somehow.…”