From the 1950s through the 1980s, he regularly appeared on television series, including appearing on The King Family Show (1965),. He made two guest appearances on Perry Mason, including the role of circus co-owner and murderer Jerry Franklin in the 1960 episode, "The Case of the Clumsy Clown". Other television appearances included The Lone Ranger, The Cisco Kid, Men Into Space,The Man and the Challenge, Hawaiian Eye, 77 Sunset Strip, Wendy and Me, General Hospital, Marcus Welby, M.D., Dragnet, Adam-12, Sea Hunt, Ripcord, Sky King, Checkmate, M Squad, Daktari, Baa Baa Black Sheep, Hawaii Five-O, Tabitha, Trapper John, M.D., Fantasy Island, Dallas, Simon & Simon, Knight Rider, Murder She Wrote, Matt Houston, Hotel, Dynasty, Falcon Crest, and dozens of others. The 1997 biographical documentary Lugosi: Hollywood's Dracula featured narration which he provided. Clarke's last appearance was in the movie The Naked Monster, a send-up of the classic science fiction films of the 1950s, in 2005.