Friday (Jack Webb) and Smith (Ben Alexander) are stymied by a series of well-planned safe burglaries, pulled off right under the authorities' noses. A clue provided by the owner of a fix-it shop turns out to be the latest in a long of false leads, but finally the investigation bears fruit when two witnesses identify a prematurely gray young man who is fascinated with all things mechanical. Based on a Dragnet radio program first heard on May 1, 1952, this episode features a cameo appearance by future TV producer Aaron Spelling as a hopped-up suspect. ~ Hal Erickson, Rovi