“After doing background checks, canvassing friends and relatives,” said Daryl taking over, “we have not found any personal or professional overlap between the victims. If the killer did know each of them, it wasn’t through any activity or person the women had in common. The only thing that links them is that they are all young, female, single and lived on the Upper West Side.”

“If they didn’t know him, why did they let him in?” said a young officer.

“Anyone can come up with a believable ruse to gain entrance to an apartment,” said Daryl. “What we can’t figure out is how the killer knows the women are alone. How does he know they don’t have a room-mate, a husband or a boyfriend?”

“Or a girlfriend,” said Heather.

“Or a girlfriend,” said Daryl, nodding.

“If he gets into their apartments with a lie, does he abandon his plan if someone else is there and move on to another victim?” said Heather looking out at the roomful of young officers, thinking they looked like teenagers. “We don’t think so.”

“Our killer appears to be enamored with rules and patterns,” said Darryl pacing in front of the map, “He works the same neighborhood, never veering further east than Central Park West and stays within a fifteen-block radius. He kills the same way, by strangulation, and always on the same day—the fifteenth of the month. Nothing is left to chance. We don’t believe he would waste time getting into an apartment, only to have his moment ruined by a room-mate or friend. If he had attempted a few kills and aborted, with all the publicity surrounding the case, someone would have reported it and we’ve heard nothing to that effect.”

“That’s right. Not a single woman has come forward and reported an attempted attack or a suspicious person coming into their apartment and then leaving on those specific days,” said Heather. “For some reason, this maniac is compelled to kill on the fifteenth of the month and somehow knows for sure the victim will be alone. But how? That’s what’s keeping me up at night.”

“If we can figure out how he selects his victims and how he knows they’ll be alone,” said Daryl, “we can catch him.”

7

Waiting for nearly twenty-five minutes in the lobby of the 24th Precinct, Zoe and Sean prepped each other for the talk with a detective.

“Remember, stay calm and tell the story slowly,” said Sean. “Don’t embellish. No extra stuff, none of your hypotheses, no tangential stories. Just the facts.”

“I know. I’ve done this before.”

“Exactly, that’s why I’m telling you to stay on message,” said Sean. “Sometimes you add personal opinion as if it were fact.”

Zoe gave him an incredulous look over the top of her mask.