Night Must Fall is a play, a psychological thriller, by Emlyn Williams, first performed in 1935.

The 1937 film of the play tells the story of an elderly woman who hires a young man as a companion, despite her niece's worries that he may be a murderer. It stars Robert Montgomery, Rosalind Russell and Dame May Whitty.

The movie was adapted by John Van Druten from the play, and was directed by Richard Thorpe.

It was nominated for Academy Awards for Best Actor in a Leading Role (Robert Montgomery) and Best Actress in a Supporting Role (Dame May Whitty).

Whitty had played the same role when the play was performed in London and in New York City.