History Film / MyStepmotherIsAnAlien

Steven Mills (Aykroyd) is a widowed scientist who is working on different ways to send radio waves into deep space. Steven accidentally sends a radio wave out of the galaxy to an alien world, which causes a disruption of gravity on her planet. One alien, Celeste (Basinger) is sent to investigate what affected the gravity and how it was done, believing it was an attack. Celeste arrives on Earth by crashing a party hosted by Steven's brother Ron (Lovitz), after which she moves in with Steven. Steven's 13-year-old daughter Jessie (Hannigan) is at first happy that her father has found someone (her mother died five years previously) but becomes suspicious of Celeste's inexperience with Earth's customs, but she cannot convince her smitten father that something is unusual about Celeste. Along the way, Celeste encounters new experiences, including love.

* AlienLunch: Celeste relies on sucking the insides of batteries for energy.

* IngestingKnowledge Celeste can open books, lay her arm across the pages, and react to the contents.

* ToplessnessFromTheBack: When Celeste is seducing Steven.

* AbsentMindedProfessor: Dr. Steven Mills manages to send radio waves out of this galaxy and to an alien planet, which causes a disruption of its gravity (though he couldn't known that there was a planet there), and is completely oblivious to Celeste's ignorance of Earth's customs, which is half this and half LoveMakesYouDumb.

''My Stepmother Is an Alien'' is a 1988 American comedy science fiction film directed by Richard Benjamin and starring Creator/DanAykroyd and Creator/KimBasinger, with Creator/JonLovitz and Creator/AlysonHannigan also appearing.

* AlienCatnip: Celeste accidetally ends up discovering that caffeine makes her drunk.

* [[ExecutiveMeddling/LiveActionFilms Executive Meddling]]: ''My Stepmother Is an Alien'' was supposed to be a film about child abuse, using the concept of an evil alien to build as a metaphor for this touchy topic. [[http://articles.latimes.com/1989-02-02/entertainment/ca-2699_1_writer-s-close-encounter Said]] screenwriter Jerico Stone: "I wanted to reach kids in a way that wouldn't make the story just a disease-of-the-week TV movie. And after certain incidents I'd experienced, I realized I could tell the story as a fable, a fairy tale that would make it easier for kids to grasp the child abuse angle." The film didn't turn out that way, for one, it was rewritten as a silly comedy instead of a horror film, at the behest of Paramount, who subsequently turned it down. It ended up at Weintraub Entertainment Group, and (like most of their output) was a flop.

* WhatCouldHaveBeen: Creator/ShelleyLong was considered for Kim Basinger's role.
* [[WhatDoYouMeanItWasntMadeOnDrugs/LiveActionFilms What Do You Mean It Wasn't Made On Drugs]]: Apart from being Creator/AlysonHannigan's film debut, the entire movie plays like a hallucinogen-fueled rewrite of ''Film/MyGirl'', except that ''My Girl'' came out three years later.

* TheInternetIsForPorn: A pre-Internet example. When Celeste at first has no idea what sex is and she asks her [[ItMakesSenseInContext talking purse]], the purse looks up the term in its dictionary, but the appropriate definition has been redacted. The purse then finds some "instructional videos"...