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 is tasked with community policing while hunting for a local vigilante. Meanwhile, Celina’s instincts are tested, and Tim and Lucy discover secrets about the two new rookies.

Ahead of Bailey's return home, John looks for clues to locate Jason Wyler. Then, Tim and Lucy swap rookies; a friendly face resurfaces at the station, and Wesley feels unsettled over Angela.

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.

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.

It’s Valentine’s Day, and Lieutenant Grey gives Tim and Lucy an unromantic assignment, while John and Celina track down a missing girl. Later, the team sharpens up for a charity gala where multiple relationships come to a head.

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.

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.