Sigourney Weaver has starred in some of the most unforgettable science fiction movies ever made, with her tough, smart characters lighting up screens since the late 1970s. Her top sci-fi films mix heart-pounding action, deep space horrors, clever humor, and big ideas about humans in the stars, making them must-watches for anyone who loves the genre.
Start with the one that launched her into stardom: Alien from 1979. In this dark, tense space thriller directed by Ridley Scott, Weaver plays Ellen Ripley, a no-nonsense warrant officer on the commercial spaceship Nostromo. The crew picks up a distress signal from a nearby planet, and what they find is a nightmare creature called a xenomorph that sneaks aboard and starts picking them off one by one. Ripley becomes the last one standing, fighting for her life in narrow corridors filled with dripping acid blood and sudden scares. The movie builds slow dread, like a cat stalking in the shadows, before exploding into chases and blasts. What makes it stand out is how real it feels—claustrophobic ship sets, practical effects with that slimy alien puppet, and Weaver’s calm strength holding it all together. She shows fear but never breaks, turning Ripley into a hero who thinks fast and survives smart. Alien won an Oscar for best visual effects and kicked off a whole franchise, proving sci-fi could be as scary as any horror flick. Fans still quote lines like “In space, no one can hear you scream,” and it’s often called the perfect blend of terror and wonder.
Ripley came back stronger in Aliens, the 1986 sequel by James Cameron that amps everything up to eleven. Over 700 filmgoers on Ranker voted it the absolute best Sigourney Weaver movie, topping even the original Alien. Waking from 57 years in hypersleep, Ripley testifies about her ordeal but learns a human colony now sits on that deadly planet, LV-426. When contact goes silent, she’s recruited to guide a team of tough space marines back there. What they face is not one alien but a massive hive of them, queen included, in a non-stop battle of guns, dropships, and power loaders. Weaver earned her first Oscar nomination for Best Actress here, chewing up the screen as a mom-like protector to a young girl named Newt amid the chaos. The film shifts from horror to full action blockbuster, with iconic lines like “Get away from her, you bitch!” as Ripley squares off against the alien queen in one of cinema’s greatest showdowns. Practical effects shine again—pulsing hive walls made of foam and horse innards, plus those Oscar-winning visuals that make the xenomorphs leap off the screen. It’s got heart too, exploring motherhood and corporate greed in space, all while delivering pulse-racing sequences that influenced games like Dead Space and movies like Edge of Tomorrow.
The Alien saga didn’t stop there for Weaver. She returned as Ripley in Alien 3 from 1992, directed by David Fincher in his gritty debut. Stranded on a prison planet full of rough inmates who hate women, Ripley crashes with an alien facehugger already aboard. This one’s bleaker, focusing on sacrifice and fate as Ripley grapples with a secret inside her that could doom humanity. No marines this time—just raw survival against a stealthy xenomorph stalking industrial halls. Weaver carries the weight, her performance raw and emotional, showing Ripley’s weariness after years of fighting. Fans debate it as the darkest entry, with moody lighting and a bold ending that shocked everyone. Then came Alien Resurrection in 1997, directed by Jean-Pierre Jeunet, where a cloned Ripley wakes up 200 years later on a military ship experimenting with xenomorphs. She’s part alien now, with weird new powers, teaming up with space pirates to stop a queen from escaping. It’s weirder and funnier than the others, full of quirky French flair, basketball-playing aliens, and Weaver’s sly, enhanced Ripley outsmarting everyone. These four films cement Weaver’s Ripley as sci-fi’s ultimate survivor, blending brains, bravery, and a bit of the monstrous.
Jump to 1984 for another classic: Ghostbusters, where Weaver steals scenes as Dana Barrett, a regular New Yorker whose apartment becomes a gateway for ancient evil. Directed by Ivan Reitman, it’s a comedy about out-of-work scientists Bill Murray, Dan Aykroyd, and Harold Ramis turning ghost hunters in New York City. Dana starts seeing weird visions and gets possessed by Zuul, the “Gatekeeper,” leading to that hilarious line, “I want you inside me.” Weaver nails the shift from posh cellist to wild demon lady, her possessed glow and growls contrasting her usual poise. Ranked third on Ranker’s Weaver movie list with over 200 votes, it’s pure fun—proton packs zapping slimers, the Stay Puft Marshmallow Man stomping Manhattan, and a score that became iconic. Weaver’s role grounds the silliness, making Dana the human heart in a film that’s equal parts laughs and spectacle. She even pops up in the 2016 Ghostbusters reboot by Paul Feig in a small cameo, linking back to the original magic.
For pure sci-fi comedy gold, Galaxy Quest from 1999 is unbeatable. Weaver plays Gwen DeMarco, a faded TV actress from a fictional 80s space show called Galaxy Quest, stuck playing the ship’s computer voice who only says “shields up” or “trajectory off.” She reunites with her washed-up castmates—Tim Allen as the Kirk-like captain, Alan Rickman as the grumpy alien—when real aliens mistake their old show for history and beam them aboard a legit spaceship for help against bad guys. It’s Star Trek spoofed to perfection, poking fun at conventions, feuding actors, and nerd culture while delivering real thrills like tentacle fights and rock monsters. Weaver shines as Gwen, breaking free from her dumb blonde trope to grab a ray gun and save the day, proving she’s as heroic as Ripley. She later talked about loving the role so much she’d do a sequel, calling Gwen one of her most iconic characters alongside Ripley. Fans adore it as a love letter to sci-fi, with lines like “Never give up, never surrender!” still chanted at cons.
Weaver dives into animated sci-fi with WALL-E in 2008, Pixar’s gem directed by Andrew Stanton. She voices the sleek EVE probe, a high-tech robot sent to check on a trash-covered Earth centuries after humans fled to space. WALL-E, a lonely trash-compacting bot, falls for her, sparking a chase across the stars. EVE’s all business at first—cold directives and laser zaps—but warms up in cute ways, her screen eyes showing sparks of feeling. Weaver’s voice gives EVE authority and sass, perfect for the role. The film mixes live-action humans on a luxury spaceship with robot romance, warning about pollution and tech addiction without preaching. It swept Oscars, including Best Animated Feature, and Weaver’s EVE stands out in nearly silent stretches driven by sound design and music.
That same year, she voiced another animated hit, The Tale o
