Officers Nolan and Harper investigate a murder which may have national security implications, while Officer Bradford must confront his past when he crosses paths with a homeless veteran.

Officer Nolan is having a particularly bad day after learning his identity has been stolen and could jeopardize his position as an officer. Meanwhile, Sgt. Grey must confront his past and testify at the parole hearing of the man who shot Grey and murdered his partner.

Officers Chen and Bradford respond to a call at the Los Angeles auditions of “American Idol,” and Officer Chen ends up facing Ryan Seacrest and the judges. Meanwhile, Chen befriends a reporter whose motives are not clear.

Officer Nolan’s relationship with his first confidential informant is tested when he discovers her back on the street dealing drugs. Meanwhile, Lucy’s fear of dating following her abduction and her intrusion into Jackson’s relationship is beginning to threaten their friendship.

Officers Nolan and Harper are tasked with escorting four juvenile offenders to a Scared Straight program at a correctional facility that quickly becomes a riotous situation. Meanwhile, Nolan is uncertain about his relationship with Grace after she fails to introduce him to her ex-husband.

Their rookie year is coming to an end and officers Nolan, Chen and West are about to be squeezed harder than ever before as their training officers evaluate whether they are truly ready for the job. Meanwhile, after one of their rookie classmates is involved in a shooting, the team uncovers some unsettling evidence .

Nolan's discovery goes much deeper than he expected and could put his life and career in jeopardy.

Nearing the end of his training, Nolan now faces his biggest challenge as a police officer yet when he must come to terms with the choices he has made in pursuit of the truth.

The team gets the true crime docuseries treatment when they analyze a recent case featuring a former child actor whose adult life has garnered him a cult following.

Harper and Nolan respond to a bank robbery in progress and realize the motives of the thief run much deeper than just needing money. Jackson and Chen’s first day riding without training officers isn’t what they thought it would be.