Frank and Garrett devise a plan to convince Mayor Chase to work better with others in order to properly run the city, and Danny and Baez try to track down a perp who vandalized several NYPD vehicles with anti-cop graffiti and made threats against officers. Also, Erin is shaken after she's in a car accident, and Eddie and Jamie argue about whether they should keep a stray dog who leads them to a crime scene.

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.

Tension escalates between Frank and Mayor Chase after Frank makes a public arrest that goes viral. Danny and Baez investigate a gang attack that takes an unexpected turn. Jamie worries when Eddie lies to him about where she's going in the evenings.

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.

Danny and Baez team up with Danny's old partner to find a copycat killer emulating a criminal's murders from a previous case; Frank and Mayor Chase battle over how best to handle the city's rising homeless population.