NBC’s One Chicago is airing its first crossover in five years tonight. Here’s how to watch the epic event featuring "Chicago Fire," 'Chicago Med," and "Chicago P.D.."

T he One Chicago universe is about to experience an unprecedented crossover event, promising to be the most ambitious in the franchise's history. For the first time, on January 29

LaRoyce Hawkins of "Chicago PD," "Chicago Fire's" Miranda Rae Mayo, and Darren Barnet from "Chicago Med" talk about the first Wednesday night "One Chicago" crossover event in more than five years. The casts of all three shows will combine for a full three hours of pulse-pounding prime time action.