In the wake of tragedy, LBPD training officer Traci Harmon takes on new trainee, Alex Diaz who on day one is already learning the job is harder than he imagined.

A chaotic street takeover finds the officers grossly outnumbered, revealing philosophical rifts inside West Division.

Diaz learns that Harmon has enemies within West Division, and begins to fear she cannot be trusted.

Desperate for a lead, Harmon goes off book resulting in a major breakthrough and a deadly showdown.

Back on patrol, the rift between Harmon and Diaz comes to a head.

When Diaz's family is threatened, Harmon realises she must break her own rules to fix it.