Millhauser authored "Hot Leather," the story of boxer Jimmy Dolan. He started his career as a stenographer in the advertising department of Pathe and, moved up to the script department where he worked on the Pearl White serials. Millhauser became a writer and producer for Cecil B. DeMille. During the 1940s Millhauser worked at the Universal studios on the Sherlock Holmes film series which starred Basil Rathbone and Nigel Bruce. He also co-wrote "The Scarlet Claw" which was one of the best of the Universal film series.