Lester is a clumsy and awkward TV repair man who is nevertheless gifted technically. In helping out a friend, he is drawn into a mystery involving a missing heir in a rich family. He begins to notice little things, like how much those family portraits look like him. Surely..no..he can't be...can he ?
Lester March, a 25-year-old orphan, works as a TV repairman but secretly longs to become a private eye. One night he and his detective friend, Pete Flint, watch a TV newscast in which spinster Cecilia Albright offers a reward for finding her long-lost nephew, the heir to a billion-dollar fortune. Lester visits the Albright mansion and is recognized as the missing heir by Cecilia's crooked lawyer, Gregory DeWitt, who plans to marry Cecilia and then murder her for her money. With the aid of Leopold, the sinister family butler, Gregory plots to kill Lester. They try to electrocute him, run him over with a car, toss him off a cliff, and poison him; but Lester fumbles safely through all the near-fatal mishaps. The first friend to suspect his true identity is the family nurse, Wanda Paxton, with whom Lester has fallen in love. Lester finally learns that he is the missing heir, and this knowledge causes Gregory and Leopold to redouble their murderous efforts. They almost succeed in trapping Lester in a platoon of electronically-operated lawnmowers, but Pete and Wanda arrive in time to save him and apprehend the would-be killers.
