Nancy Drew and the Hidden Staircase is a 1939 American mystery film directed by William Clemens and written by Kenneth Garnet.

The film stars Bonita Granville as teenage amateur detective Nancy Drew, Frankie Thomas as her boyfriend, and John Litel as her father.

When Nancy recognizes the dead man as the trespasser, she begins investigating, dragging her boyfriend Ted Nickerson into one predicament after another, eventually getting him fired and jailed.

Nancy's friends George and Bess were eliminated completely, "mystery elements were downplayed, plots simplified, and the romance spiced up.

"[5] To promote the film, Warner Bros. created a Nancy Drew fan club that included a set of rules, such as: "Must have steady boy friend, in the sense of a 'pal'" and must "Take part in choosing own clothes.