The Adventures of Leonidas Witherall, or simply Leonidas Witherall, was radio detective series based on the character created by Alice Tilton (the pseudonym of mystery writer Phoebe Atwood Taylor). Walter Hampden starred as Leonidas Witherall, the William Shakespeare look-alike who worked as an instructor on a boys’ school in New England. Witherall was also an amateur detective and an author at the same time. In the series, he wrote the "popular Lieutenant Hazeltine Stories."

The show first aired on Mutual Broadcasting on June 4, 1944, every Sunday evenings for half an hour. It ended less than a year later, on May 6, 1945.