Part 1 of a crossover with Grey's Anatomy. When Theo and Vic hit a relationship milestone, Vic is forced to reckon with her feelings about commitment. Andy takes refuge at Dean's home and helps care for Pruitt, while Dean considers a new potential ca... (more)reer opportunity. Meanwhile, an explosion rips apart a neighborhood and changes the lives of our firefighters forever. The crossover continues on Grey's Anatomy S18E05: Bottle Up and Explode! (2).