The officers of the Boston Police Department live in the city they are dedicated to protecting, working to balance fighting crime with finding time for family. For the department's Gang Unit, the target is a well-known figure whose capture becomes personal. Meanwhile, the Fugitive Unit cases the streets of Charlestown for a local suspect wanted on charges in New Hampshire. And on-duty Patrol Officers drive through the city streets, encountering an assortment of characters and challenges on every shift.