My Stepmother Is an Alien is a 1988 American comic science fiction film directed by Richard Benjamin. The film stars Kim Basinger as Celeste, a extraterrestrial woman sent on a secret mission to Earth, after her home planet's gravity is mistakenly disrupted by Steven Mills (Dan Aykroyd), a widowed scientist raising his daughter Jessie (Alyson Hannigan) as a single father.
The film's screenplay was written by Herschel Weingrod, Timothy Harris and Jonathan Reynolds, based on an earlier script by Jericho Stone, who originally pitched the film to Paramount Pictures as a drama which would serve as an allegory about child abuse. When Paramount optioned the story, they suggested that it would be more believable as a comedy. The film was unproduced for four years until Weintraub Entertainment Group put it into production in 1988.