The movie is based on the 1961 novel by Leo Rosten. It was loosely based on the World War II experiences of Rosten's close friend Ralph Greenson, M.D., while Greenson was a Captain in the Army Medical Corps supporting the U.S. Army Air Forces and stationed at Yuma Army Airfield in Yuma, Arizona. Greenson is well known for his work on "empathy" and was one of the first in his field to seriously associate Post Traumatic Stress Disorder with wartime experiences. He was a director of the Los Angeles Psychoanalytic Institute and was a practicing Freudian. Greenson is perhaps best known for his patients, who included Marilyn Monroe, Frank Sinatra, Tony Curtis and Vivien Leigh.