American journalist, short-story writer, and film scenarist. Duffy was editor of Redbook magazine and a most prolific contributor of short stories to it and other serial magazines. He had written over 200 stories by the age of 23. His popularity as a writer led to employment by First National Studios as a scenario and title writer in 1919, and he wrote for dozens of films before dying suddenly at the studio while dictating a script. He was 32.