Synopsis

During the first part of the crossover event linking *Law & Order* with *Chicago* One, Firehouse 51 responds to a house fire and rescues the homeowner from the cellar. The rescued individual clutches a box of uncertain origin, prompting Lieutenant Severide to involve Sergeant Voight and Detective Lindsey in a subsequent investigation. The crossover concludes on *Law & Order: Special Victims Unit*, Season 16, Episode 7, "Chicago Crossover (II)," and *Chicago P.D.*, Season 2, Episode 7, "They'l