Officer Nolan and the entire team are in a desperate search to rescue Officer Chen after her abduction and must attempt to get Rosalind to help them in their search. Meanwhile, after Officer Lopez discovers Wesley unconscious from a dangerous cocktail of alcohol and pills, she is forced to keep him close by.

Officer Nolan gets a lesson in respect after his arrest of a gang member leads to a free-for-all on his life. Meanwhile, Officer Chen and Officer Bradford pull over Mario Lopez, who thinks he can talk his way out of a traffic violation.

Officer John Nolan is once again face-to-face with serial killer Rosalind, and she wants him to know she's not done with him yet. Meanwhile, officers Bradford and Chen work undercover with Detective Lopez and the Las Vegas Police Department to arrest leaders of a major criminal enterprise.

After one of their own is shot, the team suffers a series of close calls and realizes their division may be a target for a group of masked assailants.

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.

Officer John Nolan is moving closer to his new role as a training officer. In preparation, he is tasked with overseeing Officer Aaron Thorson and must uncover the truth about another officer’s suicide. Meanwhile, Lucy’s successful undercover assignment earns her an invitation for specialized training in Sacramento and she must decide if this is the path she wants to take.

The team investigates a pattern of kidnappings which leads them to a discovery that hits close to home with one of their own. Meanwhile, Lucy and Tim’s relationship is put to the test as they begin to feel the hard hours of their jobs.

Officer Bradford’s wife, Isabel, is found shot but alive and he vows to track down the man responsible. Meanwhile, Officer Nolan must protect his home and the truth after a home invasion attack.

An emergency alert of an impending missile attack sends Los Angeles into chaos and uncertainty, while the officers each try to keep the peace and deal with their own disasters.

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 Tim Bradford’s ex-wife returns and asks the team to help her save someone from her undercover past. Isabel’s return also creates additional pressure in Lucy and Tim’s relationship as they assist in the search.

Officer Nolan gets off to a rocky start after being introduced to his new training officer, Nyla Harper, who has an unconventional approach to police work after her stint as an undercover detective. Meanwhile, Officer Bradford struggles to think of an appropriate birthday gift for Rachel, and Officer Lopez finds herself navigating a case that triggers a personal memory.

Officer Nolan and team are charged with escorting a notorious female serial killer to the graves of her previously unrecovered victims. However, when they arrive, they unearth even more than they expected. Meanwhile, Officer Chen meets a seemingly perfect man who sparks her interest, and Officer Lopez worries about Wesley as his PTSD continues to increase.

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.

Officer Nolan and team are on a hunt to retrieve a buried stash of gold before any treasure seekers get hurt. Meanwhile, Bradford is tasked with encouraging the oldest cop at the station to retire and invites him to ride with him.

Nyla remains suspicious of Liam Glasser as a wildfire erupts, causing chaos in the city. Meanwhile, James tries to help a friend, and Seth makes a costly mistake, putting two of their own in danger.

Starting over isn't easy, especially for small-town guy John Nolan who, after a life-altering incident, is pursuing his dream of being a police officer. As the force's oldest rookie, he’s met with skepticism from some higher-ups who see him as just a walking midlife crisis. Throw in a workplace romance, a hostage situation, and some tough love from their new training officers, and the latest Los Angeles police rookie class has an uphill battle ahead of them.

The rookies are really put to the test when their training officers accompany them out of uniform for Plain Clothes Day, which forces them to make all the decisions while on patrol. Meanwhile, Officer Nolan tries to prove he has been progressing faster than the other rookies to justify his desire of becoming a detective within five years.

Officer Nolan kicks off his birthday by babysitting a crime scene at a law office. Meanwhile, Officer Bradford and Officer West are set to receive special awards, and Sgt. Grey rides patrol with Officer Harper after she requests an early annual evaluation.

Officer Nolan and the entire team race against the clock to locate Lopez after she is kidnapped on her wedding day, not only to save her life but her unborn child’s.

Now that John Nolan knows about Bailey’s past, he must decide if they still have a future. Meanwhile, when a plane crashes in the middle of the city the team races to find out why.

Sergeant Grey supports Officer Nolan’s desire to become a training officer and offers to ride with him for the day to get him ready. Meanwhile, Tim and Lucy must manage expectations in their respective relationships as they decide on their plans for Mother’s Day and a romantic vacation.

Officer John Nolan is forced to spend a week in solitary confinement in a quiet border town with a young local officer who is in need of some training. Meanwhile, Sergeant Bradford and Officer Chen discover that looks are deceiving and go undercover together in a possible drug trafficking case.

Nolan and Bishop respond to a silent alarm call at a local convenience store where two men are attempting to rob the place. Bishop helps coordinate a drug bust that hits a little too close to home for Bradford.