During the late 1940s and early 1950s, he worked under his real name Bob Brown as a radio announcer at WANE in Fort Wayne, Indiana. He also was active as an actor in a Fort Wayne theater group. Lansing first appeared on Broadway in the play "Stalag 17" (1951) directed by José Ferrer, replacing Mark Roberts in the role of Dunbar at the 48th Street Theater. His rugged good looks, commanding stage presence and stentorian voice earned him continuing stage work and throughout his film career he periodically returned to the New York stage, making his last such appearance in 1991.