His first Broadway role was in "The Life of Galileo" (1947). His first movie role followed in "The Frogmen" (1951). As a young studio contract player, Stevens had little choice in the jobs he took. He was in movies that included "Phone Call from a Stranger" (1952), "Wait Till the Sun Shines, Nellie" (1952), and "Gorilla at Large" (1954). His most memorable movie role was probably that of "Doc" Ostrow in the science fiction movie "Forbidden Planet" (1956). He also had a supporting role in "The Barefoot Contessa" (1954) with Humphrey Bogart.