Shockwaves ripple through the Reagan family when Danny discovers that their newest family member Joe is working undercover for the ATF to bring down a gun-running organization.

The Reagans band together to prevent Joe from being killed in the line of duty like his father when they fear that his cover has been blown within the gun-running outfit he’s helping the ATF bring down.

Business becomes personal for Frank and his team when Baker is assaulted on the street, as well as for Erin, when she asks her ex-husband to represent a defendant she’s prosecuting. Eddie wonders if she’s being too stubborn after she publicly undermines one of Jamie’s decisions at work. Danny and Baez investigate the attempted murder of a couple with big secrets.

Danny and Jamie combine forces to convict a notorious drug lord, as Erin nervously awaits the Governor's selection for the new District Attorney. Frank and his grandson Joe face a difficult decision as they navigate their new and complicated family ties.

Jamie refuses to explain why he contests the arrest report of a fellow officer who was assaulted in the field.

Frank struggles after Joe's lineage as a Reagan is revealed. Erin and Anthony receive gift-wrapped evidence. Danny's opposition to authority clashes with Jamie's adherence to the rules, as both work to solve a murder.

Erin is conflicted by the weight of her authority in the sentencing of a man who is guilty of vehicular homicide. Danny and Baez pursue a rideshare rapist. Jamie and Eddie team up to aid a fellow officer when his partner is shot on the job.

Eddie and her partner are heralded for their bravery after stopping an active shooter — until a civilian comes forward to accuse them of faking the incident as part of a government conspiracy.

After Danny witnesses a drive-by shooting, he butts head with the detective assigned to the case. A childhood friend of Jamie's is convinced that she has single-handedly solved a cold case murder.

Erin tries not to feel overpowered as her new boss shadows her at work just as she's trying to get a nervous eye-witness to reveal the identity of who shot her boyfriend. The serial killer who previously held Danny and Baez hostage resurfaces, and when Jaime arrests an intrusive reporter who appears at a series of store lootings, it leads to a standoff between Frank and the Attorney General.

Baez confides in Danny and asks for his help in proving her innocence after she finds a corpse in her front yard. Erin struggles to find a peaceful solution when she receives harsh case notes from her boss. Jamie and Eddie butt heads over the handling of a young cop’s punishment. Frank makes his whole team attend therapy after Gormley exhibits troubling behavior.

Frank asks Erin to liaise between him and Governor Mendez regarding policy reform he privately backs, but can’t publicly support, because it goes against police rank and file. Danny and Baez become enmeshed in the world of competitive gaming when a high-profile video game streamer is murdered. Eddie and Witten suspect a live-in nanny is being abused after she approaches them on the street for help.

Frank and Garrett quarrel when Garrett refuses to walk back a quote he provided to a local newspaper. Danny and Baez discover a connection to a feud between local residents and city-sponsored hotels for the homeless while investigating a murder. Anthony is mistaken for a mafioso. Eddie pressures Jamie to take a love language quiz.

The Reagans confront hard choices on the job when Frank deals with a police captain who's losing his grip over his precinct. Danny faces backlash from Baez and Internal Affairs over a tough call he made in the field.

Frank takes matters into his own hands to save Gormley's career when complaints against him become public knowledge. Danny and Baez learn to be allies when the transgender community comes under attack.

Amidst a shifting political climate, Frank goes head to head with City Council Speaker Regina over protests against police brutality. Jamie and his nephew Joe work together to locate Danny and Baez when they go missing while searching for a killer. Eddie steps up to help an abrasive woman find her father's body after it was misplaced.