Little orphan Toby Tyler (Kevin Corcoran) runs away to join a traveling circus following a quarrel with his foster parents, Aunt Olive (Edith Evanson) and Uncle Daniel (Tom Fadden). Under the big top, Toby is exposed to a magical new world that includes a wacky chimpanzee named Mr. Stubbs. But the boy's friendship with paternal candy seller Harry Tupper (Bob Sweeney) is considerably less endearing -- especially when Tupper starts showing his mean-spirited true colors.