 After directing and writing for the stage in New York , Rossen moved to Hollywood in 1937 . There he worked as a screenwriter for Warner Bros. until 1941 , and then interrupted his career to serve until 1944 as the chairman of the Hollywood Writers Mobilization , a body to organize writers for the effort in World War II . In 1945 he joined a picket line against Warner Bros. After making one film for Hal Wallis 's newly formed production company , Rossen made one for Columbia Pictures , another for Wallis and most of his later films for his own companies , usually in collaboration with Columbia . 
