The film's title refers to William Shakespeare's play 'The Tragedy of Macbeth' (Act I, Scene 5), in which Lady Macbeth invokes the powers of darkness in preparation for committing murder, by saying: "Come, you spirits / That tend on mortal thoughts, unsex me here / And fill me from the crown to the toe top-full / Of direst cruelty...".
Cast members Demi Moore and Bruce Willis were married at the time that this movie was made and first released.
The film's director Alan Rudolph has said of this movie: "No one really knew what the ending would be. A half-day before we shot it, we got together and decided what the ending should be."
Alan Rudolph replaced Claude Kerven as the film's director. Original director Claude Kerven was allegedly fired before filming began and was eventually replaced by Alan Rudolph. According to an article published in the 14th March 1990 edition of show-business trade-paper 'Variety', Kerven quit the shoot at the end of the first week of filming and received just a credit for screenwriting.