It's been four months since Harlee was abducted and Wozniak was shot and they are both back to work.

Harlee, Woz, and Loman stumble upon a shooting at a diner where five people, including an undercover police officer, Det. Parker, from the Intelligence Unit, are killed. Harlee and Loman chase separate suspects out of the diner. 

Loman loses his suspect in the dark, while Harlee finds hers and shoots him because she mistakenly sees him as Agent Stahl. Loman covers for her, leaving a drop gun at the scene because the man was unarmed. 

Nava finds Harlee listening to the 911 call Stahl made while she bled out on the grass. Nava knows she keeps seeing Stahl and that she continues to wonder why he made the call to save her life. 

Harlee interviews the prostitute that Stahl paid to impersonate her. She says that Stahl says her as the good girl just trying to survive. 

Tess and Tufo are back in uniform after a disciplinary demotion. Wozniak still expects them to help him track down Quince, but the team has been broken up and they have their own assignments. 

Wozniak visits the boy who shot him in juvenile detention to play chess. He doesn’t blame the boy, he blames Quince who is in hiding. 

At Det. Parker’s funeral, Loman notices his partner, Det. Brandon Cole, arguing with another cop, Det. Theo Bennet,  who happens to be the suspect he chased out of the diner after the shooting. Harlee talks to Cole who admits Parker was meeting the dock worker Harlee shot and another one named Orlando Carter, but Orlando got spooked and ran. 

Harlee and Loman track down Orlando, but the Intelligence Unit wants him. Ramsay has Quince and they tell Wozniak they are willing to make a trade, but it’s clear they plan to kill Orlando. At the last minute, Harlee decides not to turn Orlando over to Intelligence, and Woz doesn’t get Quince.  She brings Orlando to Nava instead.

Some time in the future, Detective Harlee Santos testifies to charges of obstruction, racketeering and murder within Wozniak’s anti-crime unit.

Later, Harlee rushes to meet Nava and Orlando but thinks she spots Stahl again and gets sidetrack. By the time she get’s to Nava’s, both he and Orlando have been shot and killed.