As the Strike Team tries to end a race war between Blacks and Mexicans, Dutch and Claudette investigate a riot at a high school that also stem from racial tensions. Meanwhile, Vic is encouraged to accept an early retirement package as the Department attempts to improve its image, and Lem gets an unexpected visit from IAD. Julien tries out his new role as training officer for Tina, and Danny refuses to disclose the father of her baby.

Lem's loyalty to Vic is tested when he's interrogated by Lt. Kavanaugh and Aceveda about the Strike Team's corrupt past. Meanwhile, the Strike Team investigates a multiple homicide and extortion scam, while Dutch and Claudette suspect a womanizing preacher of attempted murder. Plus, Tina shows she's unable to hold her own on the street, causing problems for Julien and Danny.

While the Strike Team figures out their next step concerning IAD's investigation into Lemonhead, they put Tina undercover to help bust a sex trafficking operation. Meanwhile, Dutch feels betrayed when Claudette re-opens one of his cases. Plus, Kavanaugh shows up at the barn to visit Vic.

As Becca contemplates whether or not to represent the Strike Team, Vic discovers the truth about Emolia. Meanwhile, Dutch and Claudette investigate a case of road rage that escalates to a double murder. Plus, Julien and Tina's relationship continues to deteriorate, and Corrine has a confrontation with Kavanaugh.

Kavanaugh bugs the Strike Team's clubhouse in order to get his stalled investigation back on track, while Vic and the guys try to put an end to a deadly prescription drug ring. Meanwhile, Dutch tries to discover Claudette's secret as they work a missing person's case.

The walls close in on Vic when Kavanaugh invades the Barn and sets up office. Meanwhile, an elusive serial killer comes back into Dutch and Claudette's lives. Plus, Tina's discovery of Julien's homosexual past adds a whole new level of tension to their relationship.

The Strike Team solidarity begins to crack under Kavanaugh's constant scrutiny. Meanwhile, Vic and his guys consider a potential job offer from another police division. Plus, Claudette's grueling effort to break Kleavon Gardner takes a toll on her health.

As Kavanaugh deals with the emotional circumstances surrounding the return of his ex-wife, his obsession to take down the Strike Team comes to a head as he forges an unlikely alliance with Antwon Mitchell.

With their finances frozen, Vic and his guys are forced to find other means to bail Lem out of jail. Meanwhile, Tina's future at the Barn is in doubt when she jeopardizes the safety of an undercover detective. Plus, Corrine confronts Danny about her baby's paternity.

While Lem Prepares to plead guilty to the heroin charges, Vic strikes a deal with Antwon Mitchell that will guarantee Lem's safety in prison. When the deal unexpectedly goes awry, Vic takes drastic measures to protect Lem. Meanwhile, a betrayal and uncontrollable circumstances threatens to destroy Ducth and Claudette's longstanding friendship. Plus, Julien is instrumental in closing the glory hole' case.

Vic arranges to get Lemonhead safely out of the country and set up a new life for him in Mexico. Aceveda and Kavanaugh, sensing a last shot to put Vic in jail, join forces and conspire to nail Vic for harboring a fugitive. Meanwhile, in the midst of still being upset with Claudette, Dutch files for a transfer. Plus, Danny confronts her baby's father.