Magda and Jinny's investigation into the death of a college student exposes the rampant homophobia in the victim's fraternity. The case touches a nerve with Jinny, whose own brother's coming-out unleashes a fury of prejudice in her family. CD and Angela look into a case of alleged elder abuse and a shocking development causes them to question their earlier decisions. Angela learns of CD's marital woes. Kate and her younger boyfriend fight about the state of their relationship, which she wishes to keep secret.

Magda is hurt and held at gunpoint.

Jinny's Sponsor Goes off the Wagon. The Assistant to a private eve is dead.

Jinny learns of and meets her half sister for the first time. Magda and Gabe may have to donate bone marrow to save Ben's life. Ben wonders if he will die of Leukemia. Jinny is mad at her dad because of his other daughter. Kate's boss finds his name on a list.

Jinny won't let anyone help her stop drinking, The case of a dead lawyer has cops trying to figure out how he died.

Kate is up for Chief Of Police again, Will an image change help Kate keep her job?

Internal affairs looks into whether Jinny followed police procedure in an incident in which she shot the man who killed her brother (in the season 3 finale). Raina must testify about her part in the incident and is faced with a serious decision. Nate and Raina look into a suspect's hunger for sex possibly linked with a murder.

Reagan continues to find evidence to prove her son's innocence. When Reagan and Kate try to interview him in prison they don't get much information out of David as to whether he killed Mary O' Reilly. Stacey is asked to help her friend track down his missing sisters. Stacey learns that the missing sisters came from Chechnya .

After the sisters of Stacey's friend are located in a truck inside the truck four bodies are found dead due to dehydration. Stacey 's friend is asked to see if he is sister Katrina is one of the bodies in the truck. Miquel tells Magda that Katrina is still missing.

Reagan goes to visit David who questions whether he killed Mary and wonders what might happen if he is convicted of the murder.