The episode begins with ADA Barba rehearsing with Detective Cassidy, who will be testifying in the Bart Ganzel case. A woman comes to the station and tells Nick that she was raped by a cop. The woman is claiming Cassidy raped her when he was working undercover four years ago. She never saw him again until she recognized his photo in the papers about the Ganzel trial. Munch feels a woman showing up and claiming something like this, right at the time when Cassidy is going to testify against Ganzel, is too much of a coincidence.
Munch and Nick pay Cassidy a visit at home and tell him to come along with them to the station. He says he is busy. They are shocked to see Olivia coming out of his bedroom. The next day at the station, Nick shows Cassidy the photo of Heather Riggs, the woman who is accusing him. He recognizes her and says she was a hooker. Nick says Heather is claiming she was pushed into hooking by a pimp named Andre Larouge and he had Cassidy break her in. Cassidy says she is lying and angrily walks out. Nick is angry that Olivia didn’t tell him about her and Cassidy. Olivia says she didn’t because it isn’t a big deal and it’s none of his business. Cassidy tells Olivia that he is being framed for rape and she is shocked to hear it. She asks him for the details.
Olivia and team decide to discreetly look into this issue although it’s being handled by the IAB. Nick informs them that Heather works at a pole dancing studio as an instructor. Finn and Rollins decide to pay the studio a visit. They talk to the manager there and he says that Heather is a really popular instructor because she is good at her job. Rollins notices from the schedule that Heather works at the studio only two days a week. Rollins and team find out that Heather is really close to Bobby Navarro, the manager. Navarro has a police record for minor offences and is a chronic gambler. They find out that Navarro had visited Ganzel in prison two days before Heather met Nick. They conclude that Ganzel paid Navarro to frame Cassidy.
Olivia and Nick talk to Barba about this and he says that he already knows. Barba says Navarro visiting Ganzel doesn’t prove Cassidy is innocent. He says Andre and another hooker who used to work for him have both confirmed that Cassidy went into a bedroom with Heather and didn’t come out for two hours. Heather has also described in detail how Cassidy raped her. She even talked about a scar on Cassidy’s inner thigh. Olivia is shocked to hear this because she knows about the scar. Barba says Cassidy will have to face trial, so that it doesn’t look like the department is being lenient with one of its own. In court, Cassidy gets bail and is told to surrender his passport. An ADA named Strauss, who is from a different county, will be the prosecutor.
Olivia talks to Cassidy and he says that he doesn’t know how Heather found out about the scar. He says he simply talked to her for the two hours he was in the bedroom with her because he didn’t want to blow his cover. During the trial, Heather reiterates her accusation. Cassidy’s lawyer brings up the Navarro-Ganzel connection, but Heather denies it outright. The lawyer also tells the court that she is suing the city for what happened to her. Heather yells that she was raped and someone has to take responsibility for that.
The hooker who saw Cassidy go in with Heather is called to the stand. She admits that she didn’t hear or see them having sex and neither did she hear Andre telling Cassidy to break her in. Munch tells Cassidy that Nick will be called to the stand next. Cassidy knows that Nick isn’t a big fan of his. Munch tells him that Nick too has worked undercover for years and knows exactly what Cassidy is going through. Nick is questioned by Strauss and even his most objective answers are twisted around by Strauss to make Cassidy look bad. Cassidy’s lawyer, in order to prove that an undercover cop has to do certain illegal things to look convincing, brings in a woman who is the sister of a drug lord. Nick had slept with her during his undercover days.
Nick tries to talk to Cynthia, the drug lord’s sister, outside the courtroom. She is really mad because she didn’t know that he was a cop and was working undercover to take down her brother. He tries to apologize, but she angrily leaves. Nick realizes Cassidy revealed this information and confronts him. Cassidy says he is looking at a 10 years jail sentence, so he had no other options. Cassidy is questioned by Strauss and gives his version, but Strauss again turns the whole thing around and makes Cassidy look bad.
Cassidy’s lawyer consults with him in private and says no one believes his version. The lawyer suggests Cassidy confess to having sex with Heather and tell the court that it was a compulsion of his job. Cassidy refuses to admit to something he didn’t do. The lawyer warns Cassidy that he could go to prison. Cassidy is ready to take his chances. At the station, Munch tells Nick that Cynthia is suing him and the city for child support. She has a 9-year old son and is claiming its Nick’s. Nick is shocked to hear this and rushes out. Nick knocks on Cynthia’s door. A large man comes to the door and tells him that she doesn’t want to talk to him. He threatens to call the cops and Nick is forced to leave. Nick spies on the large man and sees that he is using Cynthia’s son as a drug courier.
Rollins informs Nick that Edwardo Chavez, the large man, is a drug dealer and Cynthia’s boyfriend. She says the police have enough evidence to nail Chavez. Olivia visits Cassidy and says what he did with Nick wasn’t right. He says his lawyer forced him to do it. Nick meets Cynthia and confronts her about what her boyfriend makes her son do. She says she doesn’t have any money or a family, so she doesn’t have options. He begs her to not let their son grow up dealing drugs. Cassidy meets Nick and tells him he is sorry about what he did. He suggests they help each other out. Cassidy and Rollins go undercover as drug dealers and meet Chavez. They tell Chavez that they need him to supply some drugs.
Munch and Nick go undercover as goons and visit Navarro. They tell him to settle his gambling debts, but he says he doesn’t have the money. They say if he can’t pay he will have to work it off. Navarro meets Chavez under a bridge. He tells Chavez to give him the drugs and shows him that he has brought the money. Chavez doesn’t know him, so he seems reluctant and starts to leave. The cops surround them before Chavez can get to his car. The drugs are found in the trunk of his car.
At the station, after a bit of persuasion Navarro admits to Rollins and Finn that he and Heather were trying to frame Cassidy, so they could sue the city for money. After hearing Navarro’s confession, Heather also admits to Olivia that Cassidy was telling the truth. The charges against Cassidy are dropped. Nick visits Cynthia and she lets him meet his son. The episode ends at this point.