Scripts tackled topics ranging from the thrilling (murders, missing persons, and armed robbery) to the mundane (check fraud and shoplifting), yet Dragnet made them all interesting due to fast-moving plots and behind-the-scenes realism. In "The Garbage Chute" (December 15, 1949), they even had a locked room mystery.

 

Promotional photos or cards were sent to viewers and listeners of the program during the time the show was on both radio and television.

Though tame by modern standards, Dragnet—especially on the radio—handled controversial subjects such as sex crimes and drug addiction with unprecedented and even startling realism. In one such example, Dragnet broke an unspoken (and rarely broached) taboos of popular entertainment in the episode ".22 Rifle for Christmas" which aired December 22, 1949, and repeated at Christmastime for the next three years. The episode followed the search for two young boys, Stanley Johnstone, and Stevie Morheim, only to discover Stevie had been accidentally killed while playing with a rifle that belonged to Stanley—who was supposed to receive it as a Christmas present but opened the box early. Stanley finally told Friday that Stevie had been running while holding the rifle when he tripped and fell, causing the gun to discharge, fatally wounding Morheim. NBC received thousands of letters, most of which were positive, according to the book My Name's Friday. There was a protest by the National Rifle Association. Webb forwarded their letter over to police chief Parker who promised "ten more shows illustrating the folly of giving rifles to children".

".22 Rifle for Christmas" was replaced as the series' Christmas story on December 22, 1953, with "The Big Little Jesus", which followed the detectives' investigation of the theft of a statue of the baby Jesus from a church Nativity scene. With its happier ending than ".22 Rifle", this episode was repeated at Christmastime the following year. The late-1960s TV version of Dragnet included a newly produced version of "The Big Little Jesus", which featured Barry Williams (later of The Brady Bunch) as one of the altar boys.