The film stars Milton Sills and Molly O'Day, taking on two roles as both the character Germaine and her look-alike sister.

Love soon springs up, and Haggerty decides to reform, returning to Major Cotton (Mitchell Lewis) with this resolution.

Major Cotton, when introduced to Germaine at the officers' ball, recognizes her as "Go-Go" (Molly O'Day), a notorious cabaret dancer, and tries to tell Haggerty who she really is.

Hard-Boiled Haggerty was based on a story by former World War I pilot Elliot White Springs, but was more of a romantic comedy than an aviation film.

[1] Aviation film historian Stephen Pendo noted that more action took place on the ground than in the air.