Season 4

While Detective Angie Flynn and Staff Sergeant Vega adjust to his new role, the suicide of an officer with whom Angie and Detective Brian Lucas worked on a crime scene turns the team’s investigation into a hunt for a cop killer.

Angie fills in as staff sergeant while investigating a football player's wife's murder.

The team goes after a killer who is spreading a lethal pathogen across the city.

Angie and Paula investigate the murder of an ex-con. Vega faces his boundary issues with Dr. Rogers and Lucas.

A murder with a familiar signature could mean a woman was wrongly convicted of a crime.

The murder investigation of a suburban mom takes a turn when her child is abducted.

Angie stays with a soldier who demands justice by taking the bullpen hostage.

Angie partners with an international agent to investigate the murder of a British politician's son.

The team goes on a hunt through the past to find the killer of a video game designer.

A woman is found nail-gunned to death. Angie embraces her relationship with Jack. Vega's frustrations force him to look for other options.

A woman is murdered with what appears to be a medieval weapon.

Angie races to catch a killer who is an expert at covering their tracks.

Three years after a killer gets away, the team reunites to close the case.