Killer Nun (Italian: Suor omicidi) is a 1979 Italian nunsploitation horror film directed by Giulio Berruti and starring Anita Ekberg, Joe Dallesandro, Lou Castel, Alida Valli, and Paola Morra. It follows a nun, Sister Gertrude (Ekberg), as she slowly descends into madness and drug addiction following surgery to remove a brain tumor, with violent consequences, while also carrying out an affair with fellow nun Sister Mathieu (Morra).
Provides examples of the following tropes:
- Adaptational Relationship Overhaul: While Sister Gertrude's real-life inspiration was alleged to have made passes on the other nuns in her convent, there is no evidence that she actually pursued a relationship with any of them the way her film counterpart does with Sister Mathieu.
- Bait-and-Switch: The entire premise of the killings at the hands of a deranged nun. Gertrude is just one big Red Herring whose declining mental state and drug addiction make her the most obvious and likely culprit. But, it turns out that her lover, Sister Mathieu, is the real killer, who's also mentally traumatized after apparently being molested by her grandfather in her youth, and kills older patients for revenge.
- Drugs Are Bad: Sister Gertrude, fearing that her health may be in decline following the removal of a brain tumor, begins stealing painkillers from the hospital where she works and soon becomes addicted, which does wonders for her mental state.
- Exactly What It Says on the Tin: It's a film about a nun committing a series of murders.
- Freudian Excuse: The killer was sexually assaulted by her grandfather when she was a child, and is murdering elderly patients as revenge.
- Gorn: One of the first signs of Sister Gertrude's declining mental state is her reveling in reading gory details of the lives of tortured saints to her patients.
- Nun Too Holy: Following surgery to excise a brain tumor, Sister Gertrude develops an addiction to painkillers and begins to act increasingly unhinged, culminating in her becoming an accessory to murder.
- These Gloves Are Made for Killin': A nun wearing pink rubber gloves commits a series of murders at a Catholic hospital for the elderly. Sister Gertrude believes, at first, that she could be the culprit. It's eventually revealed to be Sister Mathieu though Sister Gertrude also wears them to drug and abduct Johnathan so she can question him about the killings.
- Very Loosely Based on a True Story: The story is loosely based on that of Cecile Bombeek, a Belgian nun who began exhibiting aberrant behavior following surgery to excise a brain tumor, culminating in the murder of three patients at the Catholic hospital where she worked.
