After another fire hits one of the gang-run buildings, Murphy and Gideon find out that the cause is much worse than an act of gang retaliation. Meanwhile, Goss is unsure about Brandt's old service buddy, after he's accused of assaulting a customer at the bar where he's a bouncer. Goss seeks the truth and Gideon is faced with an important decision.

When a serial rapist is on the loose, Captain Conrad orders Gideon and Murphy to find the perpetrator before there are any more victims. However, after Gideon's new technology fails to prove helpful for the case, the team is forced to turn to an unexpected ally for help. Meanwhile, Ada struggles with a threatening part of her past and worries that if it resurfaces, it may be harmful.