Today, the success of NBC’s TV shows largely stems from its extensive procedural universes, “Law & Order” and “One Chicago” among them. But long before either of them premiered, NBC ran three different interconnected series that helped the network thrive.
All co-created by Jack Webb, “Adam-12,” “Dragnet,” and “Emergency!” aired as part of the same universe from the late 1960s to the late 1970s. The procedurals focused on police and emergency response teams, with “Adam-12” and “Dragnet” centering on Los Angeles Police Department officers as they investigate crimes and “Emergency!” following doctors, paramedics, and firefighters doing their jobs in the city.
Each of the three series was groundbreaking thanks to its detailed depiction of law enforcement, fire, and EMS services. Decades later, “Dragnet” and “Adam-12” are commonly ranked among the greatest police procedurals of all time, while “Emergency!” served as an inspiration for real-life medical personnel and firefighters. Webb’s NBC universe might not match the popularity of “Law & Order” and its spin-offs, though it left a lasting mark on the procedural genre.
Jack Webb’s NBC procedurals crossed over on several occasions

Just like the “Law & Order” shows, “One Chicago” properties, and other more modern procedural franchises, Webb’s NBC shows featured crossover episodes. The TV-movie pilot of “Emergency!” — titled “The Wedworth-Townsend Act” — saw Officers Pete Malloy (Martin Milner) and Jim Reed (Kent McCord) from “Adam-12” take part in a brief scene. Furthermore, “Adam-12” Season 5, Episode 4 partially took place at the hospital from “Emergency!” and a few medical professional characters made appearances. Lastly, in “Dragnet” Season 3, Episode 12, Officers Malloy and Reed showed up as witnesses to an incident of police brutality. Another crossover event occurred in “Emergency!” Season 1, Episode 12 when the Station 51 crew can be seen watching “Adam-12.” For a short moment, “Adam-12” existed as a fictional show within a fictional show.
Webb created his shared procedural universe with the intention of replicating the real-life experiences of law enforcement and emergency services in Los Angeles. The writers and cast members went on ride-alongs and spent time getting to know how their characters were supposed to function in their roles. Relating to “Dragnet” in particular, Webb once explained how his approach deviated from other shows on TV at the time. “‘Dragnet’ is a different show,” he told the Santa Barbara News-Press (via MeTV). “It always has been. Instead of the whipped cream, the gloss, and the big-name guest stars of most of the detective shows, we go for facts and instances.”
