Behind Office Doors is a 1931 pre-Code American drama film directed by Melville W. Brown, from a screenplay by Carey Wilson and J. Walter Ruben, based on Alan Schultz's 1929 novel, Private Secretary.

Still unaware of her feelings, he hires his latest party girl, Daisy (Edna Murphy), to work in the office, and report to Mary.

However, when James becomes engaged to the daughter of a wealthy banker, Ellen May Robinson (Catherine Dale Owen), that is the straw which breaks Mary's resolve.

The paper mill suffers terribly from a lack of good management, since most of James' success was due to Mary's guidance.

She is reluctant, until she discovers that James has broken off his engagement with Ellen, and upon her return to the company she is not only met with a job offer, but also a marriage proposal from him.