Happy Birthday Sigourney Weaver: Her 5 Best Sci-Fi Movies That Aren’t Alien, Ranked

Sigourney Weaver turns 77 today, and few actors have shaped science fiction quite like her. In 1979, Ridley Scott’s Alien turned her into Ellen Ripley, the survivor who outlasted a Xenomorph and redefined what a sci-fi hero could look like.

James Cameron’s Aliens then earned her an Oscar nomination for Best Actress, a rare honor for the genre at the time. But Weaver never stopped at Ripley. Over five decades, she has kept coming back to sci-fi, from cult comedies to record-breaking blockbusters.

Most recently, she joined the Star Wars galaxy as Colonel Ward in The Mandalorian and Grogu. So, to celebrate her birthday, here are her five best sci-fi movies that have nothing to do with the Alien franchise, ranked.

5 Paul Turns Sigourney Weaver Into the Alien Hunter

In Greg Mottola’s Paul, Simon Pegg and Nick Frost play two British sci-fi geeks on a road trip across America who stumble upon a foul-mouthed alien, voiced by Seth Rogen. Paul has escaped from a secret government facility, and the agents chasing him answer to a mysterious boss called “The Big Guy.” That boss is Sigourney Weaver.

The casting is a joke in itself. The woman who spent years running from aliens now spends the film hunting one down. She’s mostly a voice on the phone until the finale, where she finally shows up, only to meet a hilarious end. It sits at number five because her role is small, but it’s a loving wink to her sci-fi legacy.

4 Ghostbusters Gives Weaver the Role of a Lifetime Outside Space

Ghostbusters is more supernatural than spacey, but its proton packs, ghost traps, and pseudo-science give it a firm sci-fi edge. Sigourney Weaver plays Dana Barrett, a cellist whose apartment building turns out to be a giant antenna designed to summon an ancient god named Gozer. Before long, Dana is possessed by Zuul, the Gatekeeper, and that’s where Weaver truly shines.

She switches between a sensible New Yorker and a seductive demon with ease, and her scenes with Bill Murray are comedy gold. Dana is the reason the whole apocalypse happens. It ranks above Paul because Weaver is central to the story here. Still, its genre is a bit fuzzy, so it can’t climb any higher.

3 WALL-E Lets Weaver Command a Spaceship Without Showing Her Face

Pixar’s WALL-E imagines a future where humans have abandoned a trash-covered Earth and spent centuries drifting through space aboard a luxury starship called the Axiom. They’ve grown so lazy that robots do everything for them. Into this world rolls WALL-E, a lonely trash-compacting robot who falls in love and accidentally sparks humanity’s return home.

Weaver voices the Axiom’s onboard computer, and it’s a brilliant piece of casting. Fans of Alien will remember Ripley clashing with her own ship’s computer, so hearing Weaver become one is a sweet full-circle moment. Her role is tiny, but WALL-E is one of the best sci-fi films ever made, which is why it is third.

2 Galaxy Quest Lets Weaver Make Fun of the Entire Sci-Fi Genre

Galaxy Quest is one of the smartest sci-fi parodies ever made. It follows the washed-up cast of a cancelled Star Trek-style TV show who get abducted by real aliens. These aliens think the show’s episodes were historical documents, and they need the ‘crew’ to save them from a deadly warlord.

Weaver plays Gwen DeMarco, the actress whose only job on the show was repeating whatever the ship’s computer said. She leans into the joke beautifully, poking fun at how sci-fi often sidelined women, while still holding her own beside Tim Allen and Alan Rickman. It’s her funniest sci-fi performance, but it misses the top spot because one film simply had a bigger impact.

1 Avatar Makes Weaver the Heart of Cinema’s Biggest Sci-Fi Franchise

James Cameron reunited with Weaver for Avatar, which became the highest-grossing movie of all time. Set on the alien moon of Pandora, it follows humans who use genetically engineered Na’vi bodies, called avatars, to explore the planet while a greedy corporation mines it for resources.

Weaver plays Dr. Grace Augustine, the tough scientist who leads the Avatar Program and fiercely protects the Na’vi. Grace is the film’s conscience, and her death hits hard. Her impact didn’t end there, either. Weaver returned in the sequels as Kiri, Grace’s mysterious Na’vi daughter. That’s why Avatar takes the top spot. It gave Weaver a second iconic sci-fi franchise, something only a handful of actors have ever pulled off.

Which of these Sigourney Weaver sci-fi movies is your favorite? Let us know in the comments below!