S3, E1: Boden (Eamonn Walker) forces members of Firehouse 51 to pull themselves back together in the aftermath of a harrowing fire explosion. When Severide (Taylor Kinney) goes missing for one week too many, Casey (Jesse Spencer) works to track down his whereabouts. Meanwhile, Newhouse (Edwin Hodge) brings some unexpected news regarding one of Mills’ (Charlie Barnett) relatives while Herrmann (David Eigenberg) and Otis (Yuri Sardarov) make some new goals regarding Molly’s.