Lee entered the United States Army in early 1942. He was a member of the Signal Corps, repairing telegraph poles and other communications equipment. He was later transferred to the Training Film Division, where he worked writing manuals, training movies, slogans, and cartooning. The army classified Lee as a "playwright", making him one of the nine men in the U.S. Army were given that title. Lee returned from his World War II military service in 1945.