 Born in Winnipeg, Manitoba, Markle began his career in the early 1940s in Vancouver, British Columbia doing radio dramas with a group whose members included John Drainie, Lister Sinclair, Bernie Braden and Alan Young on such local stations as CJOR and the CBC network.During World War II, the group moved to Toronto, and Markle had a role as an actor in "Journey Together" (1946).Markle then moved to New York City, and although not listed in the credits, contributed to the screenplay for Orson Welles's "The Lady from Shanghai" (1947).