In "The Beverly Hillbillies" episode "The Dahlia Feud" from 1967, he played Mr. Ted, a large, muscular gardener who was planting dahlias for Mrs. Drysdale. In 1968, Cassidy appeared on "Mannix" in the episode "To Kill a Writer" as Felipe Montoya, on "Daniel Boone" in "The Scrimshaw Ivory Chart" as a pirate named Gentle Sam, and in two episodes of "I Dream of Jeannie" as the master of Jeannie's devious sister in the episode "Genie, Genie, Who's Got the Genie?", and Jeannie's cousin in the episode "Please Don't Feed the Astronauts".