* * *

“Tox screens came back.” Signy rushed into the room waving a printout. “Martin was negative for drugs but had a blood alcohol concentration of 0.15%.”

Martin had either driven under the influence or consumed a large whisky when he got home. They’d assumed the latter under the circumstances not that it mattered. No one had reported a road traffic accident and Martin Carstairs would never do it again.

For the last hour or so, Eban and six local cops who’d all been sworn to secrecy had been going over the evidence they’d compiled so far. It was approaching 11 PM and the cops had worked through the previous night. Everyone was flagging.

Signy handed him the printout. “Darby had traces of flunitrazepam in her system.”

Eban had figured as much. He glanced at the partition but the only part of Darby he could see, her feet, didn’t react. Last time he’d checked she’d been engrossed in academic text.

“What about the whisky bottle?”

“Nothing except good quality whisky.”

“Which suggests two likely scenarios, either Martin Carstairs roofied Darby’s drink in the hopes of making her vulnerable enough to take her home with him. Or the UNSUB roofied it to gain control of her but Martin got in their way. As Martin is dead, I’m betting on the latter. How’d they do it without anyone noticing?” asked Eban.

“They must have looked like they belonged.” Signy sat down again.

Eban looked at the timeline they’d constructed on the white board. “They had to have been inside the dance hall within let’s say an hour of Darby and Martin leaving. More likely it would be within thirty minutes of Darby consuming the drug. But she might not have drunk the drugged drink immediately if she was dancing. When did Jacqui Paulson leave?”

Signy consulted her notes. “9:30 PM.”

“Darby and Martin didn’t leave until after 11:30 PM. The whole thing stopped at midnight.”

“She could have snuck back in for a few moments when people weren’t looking,” Signy suggested.

“Or she could be working with someone else,” Allan Robertson offered.

Eban nodded. “She could have but I don’t like the other students in Darby’s lab as suspects—especially those who’ve been at the Institute from before Darby started here sixteen months ago.” Eban chewed the inside of his cheek. “It would be a hell of a coincidence that Darby just happened to work with a serial killer.” He thought it more likely the UNSUB had been drawn to seek Darby out—maybe they empathized with what happened to her last summer. Or they wanted to inflict more damage. He couldn’t afford to rule anyone out completely. Not yet.

“Was Lenny Serkoak interviewed?” he asked.

Signy frowned. “I don’t recognize the name…”

Eban opened the door and looked out at the bullpen, but it was empty except for a couple of uniforms and a desk sergeant. “I saw her at the vigil. She was here earlier making a statement.”

Signy sorted through the sheafs of paper and pulled out one. “Okay, got it. She says she left sometime before 10 PM. Grabbed a ride with an unnamed friend.”