Chicago Fire 4×22 “Where The Collapse Started” – Truck and squad are called to the scene of a building collapse that has trapped more than a dozen victims inside of the rubble. With the structure ready to give way and not much time to react, Chief Boden (Eamonn Walker) faces a difficult decision with life-and-death ramifications. In her quest to foster Louie, Dawson (Monica Raymund) throws all her energies into the bureaucratic process necessary to make it happen, but it is the helping hand of a familiar face that gives her a fighting chance. Currently on medical leave, Otis (Yuri Sardarov) swings by the firehouse and meets his temporary replacement, hoping it is just that but fearing the worst. Meanwhile, Severide (Taylor Kinney) and Kidd (guest star Miranda Rae Mayo) continue to see each other outside of the firehouse, and Casey (Jesse Spencer) and Antonio (guest star Jon Seda) find themselves at odds and tensions flare. Kara Killmer, David Eigenberg, Joe Minoso, Christian Stolte and Steven R. McQueen also star.