Cosgrove tells his daughter not to worry about the dishes. She says she's ready for her tests today so stop worrying. He says she will understand someday. She goes. His phone buzzes as she gets into her friend's car. A girl has been found with tape on her mouth. She might have been stabbed, dumped etc. Earring ripped out and clump of hair cut. An officer moves her bag which annoys Cosgrove. They find a book and realize this victim is the author.

Shaw fillis Dixon in. There is no video, no witnesses, no weapon. Wounds indicate a sharp blade. Dixon wonders if there was a ritual element. They look at her phone records. She canceled an Uber and called her roommate. A photo of her roommate shows he has an axe that culd have been the murder weapon.

Scott is shocked that Christina is dead. He was working at an axe store and bar when Christina died. He thought she hooked up with someone at the party.

The cops find out Christina had a fight with someone at the party she was at. A witness says he pushed the guy away who attacked Christina. The witness' assistant informs him he has to go. He has to get to set. He does know who the guy is who harassed Christina. It's a friend of his, Victor Bernini.

The cops look for Victor and a woman says he was supposed to meet her but stood her up. He is in the wind. The cops are looking for him and think he's a credible suspect. He's also a world renowned chef but is known for doing a lot of drugs. He also recently declared bankruptcy. Also Victor was shown in a bad light in Christina's book. He shows up at Yellow Ribbon and takes a giril hostage. Shaw and Cosgrove try to talk him down. He surrenders and is arrested.

Victor complains he doesn't remember what drugs he took. He seems surprised Christina is dead and is sure he didn't do it even though he has no memory of the night in question.

Video shows Victor was at a strip club/bar all night. ME is ready to see the cops.

The victim was strangled and burned. She was killed elsewhere and dumped in the park. She was also sedatedu. The ME has seen this before and gives the cops a case file.

Cosgrove introduces Shaw to Jerry Ryan, his mentor. He has info about a similar case. He also has several cases from all over the world like this. He has a sketch of the perp.

Shaw isn't sure all the cases are related. Cosgrove thinks Ryan has good instincts. Witnesses all describe a white dude driving a black Tesla.

Traffic cam footage finds the black Tesla, and it is registered to the actor who claimed to have run Christina's attacker off.

Ryan goes through the evidence that Niles is near every murder, but Shaw is still skeptical, despite a security photo. However, the perp and Niles have the same tattoo on their wrist.

Niles claims he gave Christina a ride home but didn't mention it because his girlfriend would be jealous. He acts super cooperative. Ryan says the car is a crime scene. Shaw says they need a warrant. Ryan says think like a cop, not a lawyer. Niles comes back and Ryan claims to see blood. They find Christina's earring in the car (but wouldn't that be circumstantial since she was supposedly in the car?) Niles is arrested.

Dixon says that Niles' knife set is missing a boning knife like the kind used in Christina's murder. Niles is arrested for murder.

Niles pleads not guilty. Samantha asks for remand without bail. For some reason even though it's an arraignment hearing, the defense attorney tries to argue his innocence. Anyway, he is remanded.

Niles' girlfriend doesn't want to talk to Sam and claims he was home all night. Sam shows her the photos of the crime scenes. Megan insists she is wrong and Niles was with her, and she will say so in court.

Price says Niles is a celebrity so people will do anything to protect him. There is no proof of where he was that night. Sam says the judge has ruled they can't mention prior bad acts. McCoy says they need to make it only about Christina then. The DAs get a notice that there is a motion to suppress.

Nolan and the defense argue but all the evidence is thrown out because of the lack of warrant. Ryan and Price argue about whose fault it is. Price says they need hard evidence now.

The cops search the park. Ryan talks about how this used to be a dumping ground for cars. They run into some guy with a metal detector who has not found a knife and rants about how things have changed. Shaw recalls that Niles owns property in the Bronx and decided to find out about it. They search a warehouse. Shaw finds a bunch of tools used in the murder, and Ryan says it smells like bleach, but there is no blood there. Ryan finds Christina's necklace. It is engraved with her name on it. Now they've got him.

Price gives an opening statement about how people like Niles from his movies but the real Niles is a sadistic predator. The defense attorney claims that they have no case and that there is a ton of police misconduct. DOn't let the cops get away with doing whatever they want. Nolan tells Sam that Cosgrove needs to talk to Christina's mother.

Christina's mother paid cash for the necklace. She wants to make sure that monster pays for what he did to her Tina. She says Jerry spoke highly of Cosgrove. He came by the other day to check on her.

Cosgrove talks to Ryan who says always stay in touch with the victim's family. Cosgrove asks why Ryan went to see Christina's mother. He thinks Ryan planted that necklace. Cosgrove says this is not the way to do it.

On the stand, Ryan testifies that Christina is not in the security footage at the subway station and that Niles' car was parked outside the warehouse when Niles was supposedly home in bed. Ryan also testifies about finding the necklace.

The defense attorney asks if Ryan is modest. He says no. She says but you didn't take credt for the necklace. She accuses him of planting the necklace and claims he hates her client. She says Christina was not wearing the necklace that night.  The defense attorney tries again and again to say Ryan planted the necklace until Price objects. She then rests her case.

Shaw tells Cosgrove if there's anything to tell him, tell him now. Cosgrove says they got their man.

The jury is back. Niles is found guilty. Christina's mother is so grateful and hugs Cosgrove. Ryan walks off.

Later, Cosgrove comes home and finds out that Ryan is there. Ryan gives Cosgrove an expensive alcohol. Frank won't accept it and tells Ryan to leave.