Politically ambitious new LAPD captain David Aceveda tries to crack corruption in Los Angeles' Farmington District by recruiting detective Terry Crowley to help him take down fellow detective Vic Mackey, leader of the Farmington precinct's Strike Team. As Vic and the Strike Team prepare for a dangerous night mission, detectives Holland "Dutch" Wagenbach and Claudette Wyms investigate a woman's murder, only to discover that her missing daughter has been sold off by the daughter's drug-addicted father to a child molester.

In a routine sweep, the Barn's detectives divvy up warrants. But when they cast their nets, they bring up far bigger fish than expected. While Vic holds a basketball star hostage to influence the outcome of an upcoming game, Dutch and Claudette nab an egotistical rapist out to impregnate as many women as possible.

After a bust on an Armenian gang's drug delivery, Julien sees the Strike Team take a portion of the drugs for themselves. Subsequently, the vehicle holding the drugs is stolen on Shane's watch, forcing Vic to track them down before Aceveda is able to pin the theft on him.

The Strike Team's attempt to play by the book comes to an abrupt end when they discover that the Byz Latz and the One-Niners are attempting to alter the balance of power by acquiring MP5s. Meanwhile, Claudette and Dutch investigate the murders and foot severance of Armenian men by the Armenian mob, a case that draws them closer to the truth behind the money train robbery.

Vic decides to use some of the money train robbery cash during a gun-running sting operation, but after it goes awry, tension within the Strike Team begins to mount as its members attempt to rectify Vic's mistake. Meanwhile, Dutch and Claudette seek the help of a college student named Esteban who was the only survivor in the murder of two Latino gang members.

Claudette gives Vic a chance to save his job if he agrees to train his potential replacement. An unsolved rape case from the past that Dutch and Claudette were working on resurfaces. Meanwhile, Aceveda meets someone that can help him further his political career.

Officers in the Barn investigate a woman's disappearance and the arrival of a large drug shipment; lives change forever.