The greatest sci-fi films of all time – according to Radio Times readers

From beloved space operas in far distant galaxies to fascinating treatises on what it means to be human, the sci-fi genre is one which has gifted us with many of the finest, most ambitious pieces of cinema ever crafted. It's a genre which allows for more innovation – both aesthetically and thematically – than just about any other, and one which continues to be reinvented time and time again.

With that in mind, we recently put a request out to our readers (via Facebook) to name what they believe to be the greatest sci-fi film of all time, and it's safe to say we were inundated with enthusiastic responses. The post has over 1400 comments and has yielded a huge variety of different films, from the Golden Age of Hollywood to the 21st century.

After sifting through those comments, we've put together a list of the films that received the most mentions, in order to determine the definitive greatest sci-fi film of all time according to Radio Times readers. You can find that list below, counting down to the overall winner and including our official reviews for each entry.

Although films from various eras were mentioned – the entries in the top 14 below span 1956 to 2014 – it's interesting that no films from the last decade, such as Denis Villeneuve's hugely acclaimed Dune adaptations, made the list. Perhaps they've just not had quite enough time to enter the all-time canon just yet, but who knows – maybe the list would look very different on a few years time.

In fact, there are all sorts of intriguing looking sci-fi films set for release this year, including the third instalment in Villeneuve's series, a new UFO flick from the legendary Steven Spielberg, and the Ryan Gosling-starring Project Hail Mary – which has been getting a fair bit of early buzz. Perhaps any of those could feature in future countdowns.

But for now, read on to find the best 14 sci-fi films ever made according to our readers.

14. The Fifth Element

French writer/director Luc Besson's wacky 1997 sci-fi The Fifth Element was the 14th most mentioned film in our post. The film – which starred Bruce Willis, Milla Jovovich, Gary Oldman, Ian Holm and Chris Tucker in its impressive ensemble cast – received somewhat mixed reviews at the time of release but was a big box office hit and has also gained a significant cult following.

RT review: Ancient evil returns to destroy the galaxy in this ultra-hip, socially conscious and clever science-fiction action adventure from director Luc Besson. Bruce Willis's laconic former government agent is forced to save the universe when the secret key to preventing its destruction literally falls into his cab in 23rd-century New York.

This superb flight of imagination soars into original terrain for an inventive rollercoaster ride and is a stunning achievement that delivers on all levels. The satire is slick, the visuals unusual and the thrills futuristic, and if the Big Apple special effects don't amaze, the camp trip to the resort planet of Fhloston Paradise certainly will. Gary Oldman’s villainous Zorg is haute-couture corruption personified. – Alan Jones

13. District 9

One of the more recent entries to make the list, this 2009 South African mockumentary about an extraterrestrial arrival was nominated for Best Picture at the Oscars after a wave of rave reviews. Blomkamp and star Sharlto Copley have frequently spoken about the possibility of a sequel – titled District 10 – in the years since, but as yet we're still waiting for the follow-up.

RT review: Seemingly helpless extraterrestrials arrive on Earth and are treated like any other vulnerable minority – as if they’re subhuman – in this startling mix of sci-fi action and trenchant social drama from producer Peter Jackson (The Lord of the Rings). By framing events as a mock-documentary set in his native Johannesburg, writer/director Neill Blomkamp makes obvious reference to the shadow of apartheid, but the film never seems preachy.

Heading a largely unknown South African cast, Sharlto Copley delivers a remarkable performance as the glib Afrikaaner bureaucrat heading up a brutal alien-relocation operation, who’s forced by escalating events into an affecting realisation of the error of his ways. It may give way to (admittedly effective) shoot-’em-up fare in the later stages, but this remains a textbook example of fantasy cinema’s ability to tackle thorny moral issues while splattering the screen with gloopy creature effects. – Trevor Johnston

12. Silent Running

Perhaps one of the more low-key entries on the list, this 1972 film from director Douglas Trumbull saw Bruce Dern star as an ecologist – and that ecological focus means it continues to remain relevant to this day.

RT review: Special-effects ace Douglas Trumbull (of 2001 fame) turned director with this ecologically based science-fiction tale. The action tales place aboard the Valley Forge spaceship, which carries the last of Earth’s plant life under the guardianship of space ranger Bruce Dern and his cute drone robots.

However, when orders arrive to destroy the cargo, Dern mutinies to preserve the wildlife. Although the film may seem rather hippy-influenced now – those syrupy Joan Baez ballads! – Trumbull creates some spectacular images and elicits a sensitive performance from Dern. Silent Running is gentle, imaginative and much admired. – Alan Jones

11. Close Encounters of the Third Kind

Steven Spielberg has given us several terrific sci-fi films, with ET the Extra-Terrestrial and AI: Artificial Intelligence among the other classics, and a new film Disclosure Day on the way. But only one of his efforts made this list – and that's the 1977 classic Close Encounters of the Third Kind.

RT review: As does the later ET the Extra-Terrestrial, this brilliantly realised suburban sci-fi saga reverses years of flying saucer attacks with the notion that visitors from outer space just might be friendly. Richard Dreyfuss strikes the perfect note of childlike inquisitiveness as the electrical engineer chosen to make contact with alien lifeforms, despite obstruction by family and government.

Director Steven Spielberg confirmed his genius for painting a convincing picture of mundane domestic life, subsequently shattered by extraordinary events (notably the terrifying kidnap of a young boy and Dreyfuss's slide into apparent insanity). The special effects are spectacular, John Williams's score is emotionally charged, nouvelle vague director François Truffaut makes an elegant UFO expert and it's impossible not to get caught up in the protracted climax. – Andrew Collins

10. Starship Troopers

In addition to its many other merits, one of the great advantages of sci-fi as a genre is its ability to use larger-than-life imagery for satirical purposes. That's arguably never been done better than in this 1997 effort from Paul Verhoeven, which takes the tenth spot in our list.

RT review: This violent adaptation of writer Robert A Heinlein's classic 1959 novel about Earth battling alien bugs is popcorn exploitation at its lip-smacking, blood-spattered best. Whether portraying the chilling spectacle of millions of ugly giant insects swarming over the planet or the astonishing intergalactic warfare, the special effects are simply outstanding.

It's when director Paul Verhoeven cuts to the teenage romance between young leads Casper Van Dien and Denise Richards that his sensational cartoon carnage comes unstuck. But the dull bits are never long enough to really matter or do too much damage to the sheer enjoyment of this absurdly apocalyptic satire. – Alan Jones

9. Forbidden Planet

Of course, sci-fi has been a key cinematic genre since the dawn of the silver screen – with Fritz Lang's 1927 epic Metropolis an early example. But the oldest entry to make it into our list is this 1956 film, which proved to be an extremely influential addition to the sci-fi canon.

RT review: What unknown terror roams the planet Altair-4, killing everyone apart from tormented scientist Morbius (Walter Pidgeon) and his daughter Altaira (Anne Francis)? Starship commander Leslie Nielsen (long before he turned Airplane! comedian) finds out in one of the finest science-fiction films ever made.

Loosely based on Shakespeare's The Tempest, which explains its overall intelligence, this 2001 of the 1950s is an enthralling eye-popper. The superb monster effects (created by Disney animators) and outstanding technology include the unforgettable Robby the Robot, the subterranean Krell city, Morbius's futuristic home and an impressive array of space vehicles. – Alan Jones

8. Terminator 2: Judgment Day

When discussing sequels that are better than the original, James Cameron's 1991 follow-up to his own 1984 film is often brought up. So it's perhaps no surprise that this film makes it onto our list rather than the first movie.

RT review: Director James Cameron piles on the hard-edged humour and rollercoaster action in a worthy sequel to his own 1984 horror fantasy classic. Adrenaline junkies get epic value for money as cyborg Arnold Schwarzenegger comes back from the future to save our world from the new T-1000 assassin (Robert Patrick), whose liquid metal shape-changing abilities set a new cinematic standard for stunning, computer graphic special effects.

Linda Hamilton turns in another terrific performance as the fiercely committed heroine who puts a necessary human face on Cameron's high-decibel mayhem and pyrotechnical bravura. – Alan Jones

7. The Thing

Possibly the best remake in cinema history, this film is one of the greatest sci-fi films and one of the finest horrors ever made – and so is very deserving of its high placement here.

RT review: John Carpenter's remake of Howard Hawks and Christian Nyby's influential 1951 creature feature is a special-effects extravaganza of the highest order. In fact, the updated screenplay by Bill Lancaster (son of Burt) sticks more closely to the plot of the classic John W Campbell short story that inspired the original movie, as the occupants of a polar research station (which include Kurt Russell and A Wilford Brimley) are menaced by an alien with the ability to change its shape and impersonate its enemies.

Carpenter stresses the slimy ET at the expense of characterisation, mood and practically everything else, yet it's precisely this one grisly facet that makes it such compelling science fiction. Even Alien can't hold a candle to the nightmarish images on offer here, so be warned. – Alan Jones

6. Interstellar

The most recent entry on our list, Christopher Nolan's epic was already a huge hit on release and has arguably only grown in stature in the years since.

RT review: Director Christopher Nolan goes to infinity and beyond with a cosmic epic that adds breathtaking meaning to the idea of a race against time. When former pilot Matthew McConaughey is asked to save the world from starvation by boffin Michael Caine, he jumps at the chance. For this is no ordinary mission – it requires McConaughey to enter a wormhole to find a planet for the human race to colonise – a journey that could take years.

Nolan's most ambitious film to date is a thoughtful sci-fi that echoes Kubrick's 2001, with fine performances from Anne Hathaway and Jessica Chastain. But holding it all together is McConaughey, who guarantees this majestic film retains a human heart. –

5. The original Star Wars trilogy

The original Star Wars trilogy as a whole was – no surprise – brought up by a huge number of respondents to our poll, with middle entry The Empire Strikes Back receiving the most individual mentions. It's our review of that classic instalment that you can find below.

RT review: Director Irvin Kershner's imaginative supervision of George Lucas's brainchild gives this second part of the first Star Wars trilogy a truly epic dimension, adding a mature, philosophical aspect to the nonstop barrage of brilliant special effects.

Events take place all over the universe – Darth Vader sends Imperial troops to crush the rebels on the ice planet Hoth, while Luke Skywalker searches out Jedi master Yoda for further instruction in the mysterious ways of the Force – and the much-loved characters are developed in intriguing ways.

Kershner darkens the imagery of Lucas's vibrant, futuristic fairy tale and deepens its narrative with provocative plot strands, giving this sequel a cynical, harder edge that lifts it above the serial roots of its predecessor. – Alan Jones

4. Blade Runner

A great example of sci-fi's ability to blend seamlessly with other cinematic genres – in this case, film noir – Ridley Scott's 1982 masterpiece was immensely influential. In 2017 it spawned a well-received sequel, Blade Runner 2049, which was directed by Denis Villeneuve.

RT review: A super Philip K Dick story about a superdick searching for rebellious replicants translates here into a violent visual eye-popper, based in a futuristic Los Angeles, which set the acid rain/neon-drenched metropolis design standard for 1980s sci-fi. As influential as 2001: a Space Odyssey and Star Wars, and as thought-provoking as the former Kubrick classic, Ridley Scott's atmospheric downer is a compelling noir thriller that pleads for harmony between man and machine.

Harrison Ford stars as the former cop assigned to track down android Rutger Hauer and his three associates. Hauer gives an exceptional performance as the blond humanoid who, like the others, has been implanted with memories of a nonexistent youth. The Director's Cut drops Ford's voiceover and actually adds more depth to the 1982 original, so the full masterpiece can shine through. – Alan Jones

3. 2001: A Space Odyssey

For many film fans, this will be the first movie that pops into their when they hear the words science fiction. Stanley Kubrick's film has lost none of its mystery in the more than 50 years since is release, containing some of the most iconic images ever committed to celulloid.

RT review: This seminal sci-fi work from Stanley Kubrick is considered by some to be less a supreme piece of cinema than an interesting, innovative product of the 1960s. But the memorable celluloid images still strongly resonate, such as the giant Starchild floating through space and the tribe of apes painfully putting two and two together following the appearance of a mysterious black monolith.

It is Kubrick's haunting, stylised combination of music (Strauss's Also Sprach Zarathustra and The Blue Danube) and visuals that gives 2001 its eerie, mesmerising quality. As a slice of philosophy on how we all got started and where we ultimately go, the movie continues to intrigue and perplex in equal measures. It’s a must-see if you never have, even though its visual impact is seriously hampered by the small screen. – Sue Heel

2. Aliens

Another sequel, and one which has amassed almost – but clearly not quite – as many fans as the film that came before it. There have been several additions to the franchise since, and despite some decent efforts, this still ranks as comfortably the best of the follow-ups.

RT review: Ridley Scott’s original outer-space nightmare set the bar high, but this sequel from James Cameron surpasses it in terms of sheer spectacle. Sigourney Weaver wakes up 57 years after the original events unfolded, only to be told that the planet where she first met the alien predator has been colonised.

When all contact with the inhabitants is lost, she's sent in with a crack squad of marines and hurtles headlong into a hi-tech house of horrors that delivers plenty of shocks and nail-biting suspense. Masterfully controlling the tension and moving the involving plot at a lightning pace, Cameron exploits everyone's worst fears and carries them to the riveting extreme in this consummate Oscar-winning fright-fest. – Alan Jones

1. Alien

We're sure there will be few complaints about the position of Ridley Scott's film at the very top of the list – a movie which expertly merged sci-fi and horror to create an experience that still ranks as one of the very best achievements in all of cinema.

RT review: Ridley Scott’s original haunted house in space thrill-ride is a bona fide classic, stunning you with shock after shock, even when the alien creature is revealed in all its hideous glory. In her breakthrough role, Sigourney Weaver plays one of the crew of a spacecraft that picks up an unwanted guest after answering a distress beacon coming from a barren planet.

The top-notch acting and imaginative bio-mechanical production design (with the alien created by Swiss artist HR Giger) succeed in flattering a script culled from many cult sci-fi movies, including It! The Terror from beyond Space and Planet of the Vampires. Scott brilliantly alternates false scares with genuine jolts, helping to create a seamless blend of gothic horror and harrowing science fiction. – Alan Jones

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