Severide finds that he shares a familiar past with Eric Whaley, the Lieutenant who was brought into the firehouse to help out. Dawson lets Shay in on her secret, while Casey deals with family issues. Meanwhile, a bad batch of heroin on the streets ha... (more)s Boden and the team scrambling, while Clarice and Shay find they have a new problem to overcome.

Christian Stolte, Joe Miñoso, Jon Seda, Kathleen Quinlan, Mike Starr, Shane McRae, Shiri Appleby, Victor Slezak, Yuri Sardarov