Two Detroit police detectives Frank and Joe kill a fellow cop Brendan McCann they suspect have been involved in criminal activity and make it look like a suicide. Neither of them seem to know that Internal Affairs has been investigating McCann. When McCann's car is finally found in the river with his body in the front seat and Frank has been pointed to lead the case, it seems that they are home clear. But when another dead body is found in the trunk, all their efforts to cover the murder up may have been for nothing.moreless
Frank and Joe's cover-up of their involvement in McCann's murder starts to fall apart when the autopsy reveals that McCann didn't drown in the river. Things get more heated up for them when the body found in McCann's trunk is identified, it belongs to an Internal Affairs confidential informant. Joe tells Frank that Katia is still alive.moreless
Joe regrets not killing Katia. Deputy Mayor yells at Lt. Dawson over the phone for not having results on McCann's murder case, so he puts pressure on Frank to get some results by the end of the day. Boyd refuses to share details from his case with Frank, but later shows him a file he has on Joe. A witness who saw two men putting McCann on the front seat before sending it to the river shows up.moreless
Frank goes to Canada to find Katia but is unsuccessful. Joe's daughter is caught stealing. Detective Khalil makes real headway with her investigation when she links her murder victim with McCann. Frank warns Maya about IA.
Police searches Billy Hobson's murder scene again. Frank and Joe come up with a plausible theory how to tie together all three murders. Dani tries to kiss Frank but is rejected. Poppa T with his crew turn on Damon and empties his safe, on their way out shoot-out occurs and Michael is shot.moreless
Frank finds Katia via videochat, but she shuts down the connection. He gets an internal source to track down Katia's chat site, but when they meet it doesn't go as he had planned. Joe puts April in Catholic school. Damon and Maya lose both the blind pig and The International.
Police searches Maya's and Damon's house. They and Damon's crew are brought in for questioning. All of them point to Michael as the killer except for one. Joe overreacts in the interrogation and gets Damon off. Boyd visits Dani at her home.
Frank testifies in court on Lady Belle case, a woman who was kidnapped and murdered. Joe notices he has a tail. Frank asks Cable to track activity on Katia's site, but he discovers that someone is watching Frank's online activity. Skelos threatens Maya's kids. Joe finds Katia.
Frank demands that Lt. Dawson to resign for leading a corrupt department, he also lets Joe know that he's turning them in. He books a flight and withdraws all his money from the bank. Then he makes a few anonymous calls to several people to inform them that their loves ones deaths were falsely claimed to be suicides by dirty cops. He also visits Mrs. Hobson and gives her the photo of Damon, a man who killed her son.moreless
Sean takes the blame for McCann's, Bobek's and Billy's murder. Boyd arrests Frank for carjacking. Damon and Nick attack Skelos. At mayor's office Boyd tells his theory on how Joe and Frank killed McCann, Bobek and Billy. Frank decides to take a psych leave.