“They haven’t caught LISK yet,” Doyle answered. Larkin was able to follow his movement through the studio by the shift in his voice and crunch underfoot.

“Is Ricky a goddamn serial killer?” Bosman asked from the doorway.

“No,” Larkin said without looking up. “Ricky is a groupie. It’s more common in women. Have you heard of Bonnie and Clyde Syndrome, Bosman.”

“Like the robbers?”

“Yes, like the robbers,” Larkin replied with a touch of irritation. “It’s the act of being aroused by a partner who commits violent crimes. Bonnie died alongside Clyde in a shootout with the police because she wouldn’t leave his side. It’s slang for hybristophilia, which is a psychological condition caused by a number of factors still being studied today. The common thread is that of an individual who is infatuated with a killer. They follow the killer’s story in the paper or attend court hearings, write fan letters, love letters, meet them in prison, some even marry the killer.”

“You want me to ask Ricky if he thinks he and LISK are in a committed relationship?” Bosman asked dryly.

Larkin finally raised his head and stared at Bosman in the doorway until he averted his gaze elsewhere. “My concern is that, in rare instances, those who exhibit groupie tendencies will start a relationship with the perpetrator in order to learn intimate details of the committed acts. It’s a way to vicariously experience the crime without having to spill the blood themselves.” Then Larkin pushed the coffee table aside, got down on his knees, and looked under the couch.

“I’ve yet to see a single connection between all this,” Bosman said, and he was probably gesturing at the room, “and your cold case.”

Doyle blew out a breath that had a hint of attitude, but said in his smooth politeness, “Larkin is suggesting that Ricky might have attacked Jessica today based on some firsthand knowledge he could have gleaned from a relationship with Andrew’s killer. Ricky might have been reenacting past murders—might have viewed Jessica as a match to previous victims. We’re not suggesting that Ricky killed Andrew twenty years—”

“Twenty-two,” Larkin corrected, his voice muffled. He’d squirmed halfway under the couch and was using his phone’s flashlight to study the underside of the furniture.

“Larkin, what the hell are you doing?” Doyle asked.

“You think,” Bosman interjected, “Ricky knows Andrew’s killer? Has a relationship with him?”

“Ricky sure has proven he’s open to being besties with a serial killer,” Doyle answered.

“But what’re you going to do, trawl every unsolved murder involving women with a box dye job?”

“Thank God we’ve got a Cold Case detective, hmm?” Doyle had tapped the sole of Larkin’s wingtip with the toe of his own in emphasis. “Larkin, I swear to God, I need a shower watching you wriggle around on this floor.”

“Just a moment,” Larkin answered.