Private Detective is a 1939 American drama film directed by Noel M. Smith and written by Earle Snell and Raymond L. Schrock.

The film stars Jane Wyman and Dick Foran and is based on the short story "Invitation to Murder" by Kay Krausse in the Pocket Detective Magazine.

When her boss insist that she testify, Myrna decides to quit her job and marry her boyfriend police lieutenant Jim Rickey.

However, Myrna is distracted when she overhears an incoming call from Millard, demanding police protection because Mona has threatened his life.

As she is telling Jim on the telephone to meet her at the office, Nat arrives and knocks Myrna unconscious and takes her to his beach house.