Fin and Carisi discuss childhood sins on the way to a crime scene. A woman apparently called 911 and when the cops got there they found a steak knife in the sink. Carisi and Fin find testicles in a jar and a man bleeding out in the stairwell.
The man's name is Jason Karr and he claims he was drinking with some women and went up to a hotel room with them and was attacked. He doesn't know how to tell his wife. Benson offers to tell the wife he was assaulted. He wonders what he needs to do next.
Benson gets a call that the charges against her were dropped and the investigation into Noah's injuries are closed. She is happy that this ended well. However, later her lawyer tells her that Noah's grandmother has been found in New Hampshire and she wants custody of Noah.
Meanwhile, the investigation leads to a woman named Julie Wade. Julie claims that she was at home with her boyfriend. The boyfriend comes in while the cops are talking to her and barks at her to get rid of the cops and make him breakfast. Julie tells the cops her credit card, which was tied to the hotel where Jason was found, has disappeared.
Further investigation shows that three women were in the hotel with Jason. Julie, Evelyn Bundy, and Nora -- the woman who called 911 in the first place. Nora is called back to the precinct, where she pretends not to recognize Evelyn. She keeps trying to evade the cops questions and eventually refuses to talk at all.
The cops find out all three women went to high school together and Jason Karr was their teacher. The women are arrested for obstruction of justice when none of them will admit to the crime. They decide to confess.
The women tell the cops that Karr sexually assaulted them all when they were in high school. Evelyn says at their 20 year reunion they all talked about it and they looked Karr up and found out where he works. They decided to confront him and things got out of hand. Evelyn admits she castrated Karr.
Evelyn is arrested and is angry because Karr raped her and is getting off scot-free. She claims she took the knife for protection because Karr forcibly raped her when as a senior in high school she confronted him about seeing other girls. Rollins thinks maybe Evelyn made this story up but Fin believes her.
Karr is arrested and his wife is angry. She says that Evelyn ruined their chances of having a family since Karr can no longer have children. Karr's trial begins and the defense attorney is hard on Evelyn. Evelyn has a conch shell that Karr gave her and angrily breaks it, cutting her hand.
After, Karr's wife brings new evidence to the detectives proving Evelyn's story -- a poem she wrote in high school. On the stand, Karr paints himself as the victim here, but Barba has him read the poem aloud. Karr claims it is just a metaphor but is forced to admit Evelyn wrote it.
Barba tells Benson he wants to make a deal and punish both Karr and Evelyn. Benson tells him they need to stand up for rape victims.
At closing, the defense attorney argues that Karr was already punished for the alleged rape when he was castrated and should not be punished now because it's not fair that he faces all these consequences and Evelyn none. Barba passionately rebuts, arguing that vigilante justice is not justice at all.
Barba wins his case, but there's more bad news ahead for Benson as there is another knock at her door. It's Sheila Porter, Noah's biological grandmother.