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.

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.

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.

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.

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.

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.

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.

As the rookies prepare for a big exam to see who moves on to the next stage of training, Officer Nolan and Officer Bishop are called to the scene of a murder and learn that the victim may be tied to a potential terrorist attack on the city of Los Angeles.

When a prison bus crashes, all units must respond as some inmates face severe injuries while others seek an opportunity to flee. In the wake of the accident, Officer Nolan tries to impress an FBI hostage negotiator while tracking down an escaped convict.

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.

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 .

In the aftermath of the assaults in the explosive season five finale, the team must now try to understand why they were targeted and if there is a bigger plan in place. Meanwhile, Nolan must survive his last shift before his wedding to Bailey.

The team mobilizes to locate a suspect after a deadly series of events affects one of their own. Meanwhile, Celina takes on her first case with Bailey's help.

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.

Officer Nolan and Celina take on a special case; meanwhile, Monica enlists help to identify her attackers. Elsewhere, Lopez and Harper discover a connection to the trail of crimes.

Following his stint at the LAPD, Wesley returns to the district attorney's office where his past connects him to the team's investigation. Meanwhile, Bailey and John have conflicting feelings over safety, while Lucy grows suspicious of Seth.

On Captain Andersen’s orders, Officer Nolan and Sergeant Grey are paired up for the day on patrol. Additionally, Nolan’s son and Grey’s daughter visit their dads on the job and see them in action. Meanwhile, Officer Chen is paired up with Captain Andersen, and Officer Bradford tells Chen to protect her at all costs.

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.

Sergeant Gray informs the rookies that they must track down a specific set of crimes in a 48-hour period in order to qualify for their final exam. Meanwhile, Officer Nolan and Officer Bishop answer a silent alarm call at will.i.am’s house.

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 Nolan mildly injures himself while chasing down a shoplifter and the local DA wants to charge the suspect with assault despite Nolan's wishes. Meanwhile, Lucy goes undercover, Lopez' wedding venue is seized by the FBI and Nolan meets his new neighbor.

Now recovering from a gunshot wound and feeling the effects of his age, John and the team welcome two new rookies and continue the hunt for two dangerous inmates with very personal vendettas following their prison escape.

The team searches for a serial killer as Nyla struggles with the aftermath following the attack. Lucy’s relationship with Seth takes a turn, while Bailey battles her fear of Jason Wyler.

On Celina's last day as a rookie, John gives her one final test. Meanwhile, Bailey makes a new friend, and Lucy places her faith in Seth for an undercover assignment.

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.