As a playwright he co-wrote several plays for the stage. His 1937 play "Goodness, How Sad" was turned into an Ealing Studios film, "Return to Yesterday" (1940), directed by Robert Stevenson. Later, he had outstanding success in London and New York with "Edward, My Son", a gripping family drama written in 1947 in collaboration with Noel Langley. Morley played the central role of Arnold Holt, but in the disappointing film version Spencer Tracy was miscast, turning Holt, an unscrupulous English businessman, into a blustering Canadian expatriate. "Edward, My Son" (1949) was directed by George Cukor for MGM-British. Morley's acting career continued with roles as a missionary in "The African Queen" (1951), "The Story of Gilbert and Sullivan" (1953), as W. S. Gilbert, and in "Oscar Wilde" (1960). In 1959 he appeared in an "Alfred Hitchcock Presents" adaptation of a Stanley Ellin short story entitled, 'Specialty of the House'.