The original Dragnet, which ran from 1951 to 1959, was the grandaddy of all TV cop shows. Without Dragnet the police drama as we know it today would have never been born. Star, producer, director, and writer Jack Webb took what was originally a radio drama and gave us a glimpse into the lives of ordinary policemen and their routine which was often boring but filled with drama and tension on occasion.
Dragnet took its scripts from real life police files. As the narration said, "The story you are about to see is true. The names have been changed to protect the innocent." The show seemed real at times and the LAPD frequently reported instances of people showing up at police stations and asking to see Sgt. Joe Friday (Webb's character). Their stock answer was, "Sorry, it's his day off."
Dragnet had a second incarnation under Webb's guidance and would have two more after his death. One in the late 80's and the other in 2002 starring Ed O'Neill. None had the impact or garnered the ratings of the original though. Perhaps Dragnet was a product of its times--the easy going era of the 1950's. Trying to update it made for interesting television at times but you couldn't duplicate the success or the impact of the original.