When a homicide case ends in a hung jury, Erin is forced to take over the case from her colleague and find a missing witness. Also, Jamie and Eddie go undercover as an elderly couple to catch a gang that is terrorizing a neighborhood.
When a prominent Alderman known for his urban revitalization efforts is killed, Intelligence looks into the corruption haunting his neighborhood. Meanwhile Olinsky (Elias Koteas) feels pressure after receiving an ultimatum from Woods (guest star Mykelti Williamson)
