Frank announces he will not endorse Erin's run for district attorney; Danny and Baez investigate a bloody crime scene at a hotel; Jamie begins a new job as a field intelligence sergeant that requires him to keep secrets from his family.

Danny and Baez investigate a series of violent robberies targeting luxury timepieces; Erin is conflicted about criminally charging a potentially innocent man; Frank is forced to reopen a case in which the officer involved was acquitted.

Danny crosses paths with a criminal from a previous case when he investigates a gang attack with a shocking motive; Frank and Mayor Chase butt heads over an off-duty cop who goes too far making a political statement.

Jamie and his new intel team officer infiltrate a high-tech car smuggling ring; Frank faces off against the city's transit chief over a program that is causing officer injuries on the job; Eddie asks Danny to help her bust a cop impersonator.

Danny partners with Texas Ranger Waylon Gates to deliver an infamous drug cartel boss to arraignment, but the mission becomes complicated when the criminal threatens to harm the Reagans; Erin takes on a highly contentious assault case.