Evil Uncle / Film

• Uncle Les in BrainDead is a repulsive sleazy Jerkass who tries to blackmail Lionel out of his mother's estate.
• Sir Edgar from Ella Enchanted is one of these to Prince Char. In grand Hamlet fashion, he murdered Char's father in order to become King.
• Michael Myers from the Halloween series tries to kill his niece Jamie in the fourth and fifth films (he succeeds in the sixth), and his nephew John in Halloween H20: Twenty Years Later. This is avoided in the 2018 film, where Michael and Laurie are no longer siblings, so Michael, while he is no less evil to them, has no relation to Laurie's daughter, Karen, or Karen's daughter, Allyson.
• Frank from Hellraiser. First, he has an affair with Kristy's stepmother, making Kristy's father's marriage an unhappy one. Later, he causes the horrible death of Kristy's father. Not to mention that it's shown that the novelty of doing it with the stepmother had worn off for him... and he's shown to take very well to the idea of turning his attentions to Kirsty. Numerous times, he's shown trying to rape her, including a scene where they kiss.
• Bo Baker's Uncle Bill from High Stakes, an abusive asshole who gave Bo his job at his news station just so he could have someone to kick around when he wasn't popping pills or drinking.
• Kevin's Uncle Frank in Home Alone treats him quite poorly, and shows no emotion when his parents leave him behind accidentally. In the sequel, he hasn't changed much, although he does mellow slightly by the end. In fact, the original draft for the first movie was going to have Uncle Frank as a straight-up villain, who hired Harry and Marv to knock over the McAllisters' house in exchange for a cut of the loot.
• The Huntsman: Winter's War: The big twist is that Freya's baby son was not killed by his father, but rather Freya's sister, Ravenna, who manipulated the events to bring out Freya's ice powers.
• Jason Voorhees is upgraded into one in Jason Goes to Hell: The Final Friday as he suddenly has more relatives and has to possess one them to return back to life properly. Oddly, when given the chance he ignores his niece and tries to possess his grand-niece instead.
• Killers of the Flower Moon: William Hale is the uncle of Ernest Burkhart, who marries an Osage woman as a part of his uncle’s plan to take her people’s land for oil.
• In Legend of the Black Scorpion, due to being an adaptation of Hamlet. Uncle kills father, takes power, tries to kill nephew.
• In The Librarian 2, Flynn's Uncle Jerry is a lovely man who Flynn idolised growing up until The Reveal when he becomes a Smug Snake out for revenge and is revealed to have killed Flynn's father.
• Lost in a Harem: Prince Ramo's Uncle Nimativ, who used a pair of hypnotic rings to steal the throne and keep everyone else in line.
• In The Northman, the Big Bad is Prince Amleth's uncle Fjölnir, who murdered his father and usurped his throne with the Scandinavian legend the story was based on being what inspired Hamlet.
• Nothing but Trouble: Prince Saul is plotting to murder his 12-year-old nephew, King Christopher, and take the throne of "Ostrovia" himself. He doesn't know about Christopher's best friends, Laurel and Hardy.
• Dastan's uncle in the Prince of Persia: The Sands of Time movie. His ultimate goal is to turn back time so that he can let his brother die as a teenager and reign in his stead.
• Purgatory: Sonny's uncle, a ruthless bandit and rapist. In the end he tries to gun his own nephew down.
• Uncle Charlie from the film Shadow of a Doubt is one of the first major examples of a psychopath in cinema and a very creepy and evil uncle.
• In Stardust, The Reveal is that the scheming and fratricidal Seven Princes of Stormhold were actually Tristan's uncles. They're not the primary villains, though. This is more obvious in The Film of the Book.
• The Fallen is this to Opimus Prime in Transformers: Revenge of The Fallen, although there might be a few greats in there, how many generations separate the two isn't made clear.
• Sam Harper of Uncle Sam is a sadistic door gunner who was shot down in Iraq, and to the horror of the rest of the Harper family goes on a psychotic murder spree from the grave.
• Uncle Silas is a 1947 Gothic Melodrama in which the eponymous uncle played by Derrick de Marney seeks to wrest Jean Simmons' inheritance from her. Released in the US in a butchered version called The Inheritance. Silas is this trope although more of the menace is provided by Katina Paxinou as the evil governess.
• Prince John is Philip of Cognac's evil uncle in Princess of Thieves, and plots to keep Philip from ascending the throne.
• Vivah: Rama's husband may be raising her niece Poonam along Rama's own daughter Rajni, but Rama has always disliked Poonam for her beauty and how she takes away from Rajni. Krishnakant even points out that Poonam is a lovely girl and Rama is the only one who has ever had a problem with her. Poonam risking her life to save Rajni is what causes Rama to finally realize how badly she's been acting.

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