Landis appeared in a string of successful films in the early 1940s, usually as the second female lead. In a time when the singing of many actresses was dubbed in, Landis's own voice was considered good enough and was used in her few musical roles. Landis landed a contract with Twentieth Century-Fox and began a sexual relationship with Darryl F. Zanuck. She had roles playing opposite fellow pin-up girl Betty Grable in "Moon Over Miami" and "I Wake Up Screaming", both in 1941. When Landis ended her relationship with Zanuck, her career suffered and she was assigned roles in B-movies.