After a brutal shooting, Burgess and Ruzek find themselves trapped aboard the busy "L" subway; as they piece together scant evidence, the team is drawn into a dark family drama; Burgess' proximity to the shooting triggers harsh memories.
Adam: I think you need to take some time; you wanna sit in the squad, if you want to call the therapist. Kim: We need to find the man who killed that kid.
Trauma has a way of trapping you without you even you knowing it's sitting there right on top of your body, weighing you down until something makes you notice, until a car backfires and you're shaking on the ground panicking because you feel liek you've just been shot again. Is that what happened?
