His films included Meet Me in St. Louis (1944), Twelve O'Clock High (1949), All About Eve (1950), The Day the Earth Stood Still(1951), Rawhide (1951), Howard Hawks' Monkey Business (1952), Earth vs. the Flying Saucers (1956), Elmer Gantry (1960), Birdman of Alcatraz (1962) and Seven Days in May (1964).
Marlowe plays a real person, the Reverend William Hyde, in the 1956 episode "Dig or Die, Brother Hyde" of the religion anthology series, Crossroads. Hyde was an itinerant prairie preacher who in the story line employs psychology to restore a woman's faith and to save her child's life. His co-stars in the episode are Alan Hale, Jr., Denver Pyle, and Ray Teal.In the unusually titled 1957 episode, "Jhonakehunkga Called Jim", set in 1883, Marlowe plays the Reverend Jacob Stucki, who is dispatched to the mission at the Winnebago reservation. The Indians, however, scorn the clergyman, who befriends a boy in an effort to prove his sincerity. Pat Hogan plays Jhonakehunkga, and Frank de Kova is cast as Black Hawk.
Marlowe made six guest appearances on CBS's Perry Mason, starring Raymond Burr. Among those roles, he was cast as District Attorney and Perry's client Brander Harris in "The Case of the Fraudulent Foto," (1959) and as murder victim Cmdr. James Page in "The Case of the Slandered Submarine" (1960).
Marlowe was also a regular on the NBC television daytime drama, Another World, the last of four actors to portray the Matthews family patriarch, Jim Matthews, from 1969 until Marlowe's death in 1982 from a heart attack at the age of seventy-one.
Marlowe was married three times:
- Actress Edith Atwater (divorced 1946)
- Actress K. T. Stevens (1946–1968) had two sons with Marlowe.
- Rosemary Tory (1968–1982) had one child with Marlowe.