Voight questions Deputy Chief Reid's motives in enacting a Violence Reduction Initiative across a neighborhood where numerous gangs are fighting for territory.

Ruzek grapples with his father's worsening condition while Intelligence searches for an elusive serial killer.

A mounting street war threatens a community-center project that Atwater is trying to get off the ground.

Intelligence makes a gruesome discovery that leads Torres to go undercover at the juvenile detention center where he served time as a teen.

With the suspects still at large and conditions worsening underground, first responders race to reach the trapped victims, while the investigation into the assailants comes into focus.

An unexpected visitor causes disruption for Ruzek and Burgess amidst an emotional investigation involving an unidentified young girl.