She had been back for months. She had finally been taken off desk duty, and put back into the field. She had dealt with her share of psychopaths, but this case was different. They knew who the perpetrator was. They knew what he liked, but they didn't know where to find him.

Frost drives her home that night. When he pulls up the curb he locks the car doors, preventing her from getting out.

"What are you doing?"

"Jane are you sure about this?"

"Really, Frost? You're going to lecture me, too?"

"I am just asking. This is dangerous. You could get hurt."

"It is part of the job."

"You have to be careful. I don't want another partner," he tells her.

"Gee, thanks. Is that supposed to inspire me to change my mind?"

"No, it's just a reminder, to be careful."

"I know what I am getting myself into, here. I want to catch this bastard."

"At what cost?"

"I'm not going to get hurt. I know what I'm doing."

"I don't think you should do this."

"Because I'm a girl?"

"That's why you should do it."

"Then why do you think I shouldn't do it?"

"Because you always wait until the last minute. You cut it too close. You try to be a hero, even if you don't want to be called that. You don't do the world any good, if you're on a slab, in Maura's morgue."

"I know that."

"This guy is a psychopath."

"I know that."

"He's a monster, Rizzoli."

"Is that supposed to scare me? We deal with monsters every single day."

"This is different. This guy is a different breed of monster. We don't know enough about him, to do this. We've been on this case for twenty eight hours. We need more time."

"More time? Frost we don't have more time. We went to seven crime scenes today. All seven of them were his. It will take Maura three days to finish all seven bodies. The bodies are just going to keep stacking up. We don't have a choice. We have to catch this guy, before we get anymore bodies, ok?"

"He's worse than Hoyt."

"I know that."

"What if we can't get to you in time? What if you aren't that lucky?"

"You'll be sitting out here, watching. Nothing is going to happen. The second that I know he's there, you'll know," she unlocks her door.

"Jane?"

"Huh?"

"Just be careful."

"Ok," she agrees.

She gets out of the car, and goes into her apartment. Frost waits, outside in his car. He watches carefully. He would have felt more at ease, if he weren't the only person available for back up. With seven bodies every member of Boston PD was either at a crime scene, or at the station, going through evidence.

Vince Korsak sifts through the crime scene photos. It was easy to tell what the victims had in common. Physical appearance. Dark hair, slender, tall, dark eyes. Unfortunately, that also described one Jane Rizzoli. Which was exactly why she had volunteered herself as bait. They knew the perp would be watching. Vince lays the crime scene photos out on the table. He tries to shake the nagging feeling at the pit of his stomach. He carefully looks at each photo. Then he sees it. All the victims had more than one thing in common. It was more than looks. It was convenience too. They all lived in apartments, which wasn't really that odd. But as he looks at the picture he realizes why. Each apartment has duct work. Duct work, and a vent large enough for someone to fit through.

He pulls out his phone. He calls another detective, one he knows will still be at the scene.

"Hello?"

"Crowe I need you to do me a favor."

"You've got something?"

"Look in the vent."

"The vent? What vent."

"The one that is large enough for someone to fit through."

"Why didn't we think of that earlier?"

"It was such chaos," Vince replies. He waits as Crowe unscrews the cover on the vent. Crowe takes the cover off the vent, and looks inside, with a flash light.

"Vince?"

"Yeah?"

"I have a couple of clothing fibers here. He was definitely in this vent."

"I want you to look through every other vent."

"Ok. Give me a couple of minutes, and I'll call you back."

"Ok," Vince hangs up.

Five minutes later Crowe calls back. As Vince picks up the phone he feels his stomach churning.

"Well?"

"We looked at the other vents earlier, for recording devices."

"You didn't find anything then."

"Because we weren't looking hard enough. All of them had duct tape in them."

"That's not unusual, it is duct work."

"It's double sided," Crowe responds.

"Double sided?"

"Maybe that's how he knew so much about his victims. He was watching them."

"I've got to call Frost."

He hangs up. His finger feel heavy, and clumsy as he tries to dial detective Frost's number. After three rings Frost answers.

"Frost," he answers.

"Any movement?"

"None, why?"

"How long has she been home?"

"An hour and a half. It's been quiet."

"Frost he's watching her."

"You think that he's already here?"

"I don't know if he's there, but I know he's watching her. We found double sided tape in the vents."

"Cameras?"

"That's what we think. It's just speculation, at this point, but we can't be too careful."

"She's going to be pissed if I blow this."

"It's better for her to be pissed, than dead."

"How did he get in?"

"The vent."

"Jane doesn't have a vent large enough for someone to fit through, in her apartment."

"Are you sure?"

"Yeah."

"Is there any other way that he could get in?"

"I don't think so."

"Think harder, Frost."

"Um... ceiling tiles. She has ceiling tiles in her bathroom."