Perhaps it was popular demand after a feature film had been released a few months earlier, but Jack Webb's seminal crime drama, Dragnet, which first transitioned from radio to television in 1952, returned to NBC in January 1967 as a mid-season replacement, and this version ended in 1970 after 3 1/2 seasons.
As before, Webb wore multiple hats as director, producer, and star, as Sgt. Joe Friday (Webb) narrated each episode. This time, Webb was partnered with Harry Morgan, who at the time was better known for his sitcom work, cast as Officer Bill Gannon. The tag team of Art Gilmore and John Stephenson were the announcers. Gilmore, to his credit, also appeared on camera periodically as a police captain.
In "The Big Explosion", Friday & Gannon have to locate some stolen gelatin dynamite. Another television veteran, Olan Soule (ex-Captain Midnight), who, like Morgan, had been busy doing sitcoms (i.e. The Andy Griffith Show) prior to Dragnet, was cast as forensic scientist Ray Murray, but also got in some time as a judge in at least one or two episodes. Murray provides Friday & Gannon with some important advice in their investigation.
As we all know, Dragnet would be reborn on the tube twice more, first in the syndicated New Dragnet in the late 80's, following Dan Aykroyd & Tom Hanks' comic homage to the series in a 1987 feature film that saw Gannon promoted to Lieutenant, and in 2003, when Dick Wolf (Law & Order) took over the franchise and remolded it as a 1 hour series starring Ed O'Neill (ex-Married....With Children) as Friday.
Here's "The Big Explosion".