As the city reels from the school bus tragedy, newly appointed D.A. Mario Siletti promises justice for the victims. Terry receives new evidence about the recent death of a cop, leading him to believe it may have been of a more insidious design. Meanwhile, the body of a young Chinese gang member found in an urban grow house, leads Hildy into the dangerous world of drugs and gang politics.

The pressure ratchets up on Terry and Hildy to discover who's behind the cop-killings. Jamie comes out swinging, making an unexpected move in her defense of Dustin. Navarro reunites with his brother, who has been recently released from prison. Meanwhile, an anonymous tip gives Raffi a potential connect for her case against Suger.