The sci-fi genre is so open to interpretation and reinvention that it has become one of the most popular mediums in which to tell original stories, because the tropes and archetypes of the genre instantly lend it a more fantastical element that opens the door for a much wider creative scope.
Sci-fi was once frowned upon as a niche that stuffier audiences wouldn’t entertain the idea of watching, but over the decades it has permeated the very fabric of pop culture and these days you can’t go anywhere without bumping into aliens, alternate universes or time travel.
Throughout the history of television, sci-fi has delivered a near-constant lineup of shows that can be deemed all-time greats, making it a very difficult task to narrow it down to the 25 best ever.
The undoubted high point of Gerry and Sylvia Anderson’s 1960s Golden Age of Supermarionation, Thunderbirds may have only run for 32 episodes and two seasons but left an indelible mark on sci-fi.
Focusing on the adventure aspect rather than the technology, the show was characterized by impressive action set pieces and surprisingly tight plotting for what was ostensibly a kids’ show.
For over half a century, Thunderbirds has endured as one of the most popular and influential works of science fiction to ever hit the small screen, appealing to every demographic in the process.
Fringe may have gotten off to a relatively slow start, but once the show found its groove the combination of the standard procedural with fantasy and sci-fi became a firm cult favorite.
Viewership figures may have dropped throughout the five seasons but the quality kept improving, and by the time the finale aired in January 2013 Fringe had built up a dedicated and loyal following.
Having the FBI investigate parallel universes is a unique hook for any TV show, and the involvement of J.J. Abrams’ Bad Robot guaranteed a mystery box packed to bursting point.
23. Babylon 5
Babylon 5 was groundbreaking in the way that it told a novelistic story on the small screen, with each episode telling one piece of a single puzzle that unfolded over five seasons.
J. Michael Straczynski’s brainchild also dealt with some heavy themes including ideas of war, peace, free will, religion and addiction, all wrapped up in an epic sci-fi drama.
The sheer depth and complexity of the narrative saw Babylon 5 gain huge cult status, and helped popularize effects-heavy TV projects while also harnessing the nascent power of the internet as a marketing tool.
22. Quantum Leap
As far as pitches go, a scientist finding himself trapped in the past with the ability to leap into different bodies on a regular basis while trying to get himself back home is a doozy.
Quantum Leap had no pretenses about being a weighty or thoughtful drama, it was sheer light and breezy entertainment and turned out all the better for embracing a sense of fun, humor and romance.
Bolstered by Scott Bakula’s charismatic lead performance and a constantly scene-stealing Dean Stockwell, Quantum Leap has remained incredibly popular and has found itself being referenced in everything from Family Guy to Avengers: Endgame.
21. Buffy the Vampire Slayer
Buffy the Vampire Slayer might be more supernatural than sci-fi, but the definition of the genre is fiction based on scientific, technological, social or environmental changes, and the idea of vampires wreaking havoc in a small down is a pretty substantial social change for Sunnydale.
One of the definitive TV shows of the 1990s, Buffy remains as watchable now as it was two decades ago thanks to a winning cast and themes that are still incredibly timely and prescient.
The fight choreography, performances and interwoven story-lines make it ideal binge watching material, and the show’s influence can still be felt all over television’s female-driven and action-orientated output to this day.
20. Stranger Things
Netflix’s marquee series may only be three seasons old, but Stranger Things has already more than established itself as an unstoppable cultural juggernaut and huge fan favorite.
An endearing blend of Amblin-influenced nostalgia and chilling sci-fi horror, the Duffer brothers have taken their unabashed love of the 1980s and turned it into must-see TV.
The young cast embodied their roles from the very first episode, and the veterans have proven to be just as reliable, and the end result has been a show that’s dominated the zeitgeist ever since the first season dropped in July 2016.
19. Star Wars: The Clone Wars
The first two seasons may have been a lot more kid-friendly, but the longer The Clone Wars went on the more it offered perhaps the most complex and intricate storytelling Star Wars has ever seen.
It might be an adventure series first and foremost, but Dave Filoni’s lifelong love of a galaxy far, far away can be felt in every single frame, in a show that fills in the gaps in the mythology to phenomenal effect.
The seventh and final season came armed with a hefty Disney Plus budget, and saw The Clone Wars go out in spectacular style from both a creative, visual and narrative perspective.
Legion may have quietly been one of the best things to ever come out of the expanded X-Men universe, as Noah Hawley’s mind-bending series threw all of the superhero conventions out of the window.
Much more an existential sci-fi than a comic book adaptation, three seasons and 27 episodes was more than enough for Legion to gain a well-earned reputation as a minor modern classic.
Visually and structurally the level of ambition was off the charts, and it was all held together by Dan Stevens’ stunning and richly layered performance as troubled protagonist David Haller.
17. The Handmaid’s Tale
Some reviewers seem to believe that The Handmaid’s Tale is beginning to run out of steam, but with a fourth season set to arrive next year creator Bruce Miller will be looking to prove a point.
The adaptation of Margaret Atwood’s dystopian novel has so far been a critical and awards season juggernaut, scoring widespread acclaim and scooping two Golden Globes and fifteen Emmys.
A combination of gripping drama and societal subtext, The Handmaid’s Tale is proof that great sci-fi doesn’t necessarily need to involve anything remotely intergalactic to draw in viewers and attain success.
Everyone seems to be firmly in agreement that The Simpsons peaked over 20 years ago, and in terms of maintaining a consistently high level of quality, Futurama might be the better Matt Groening show.
The series may have been canceled at both Fox and Comedy Central, but over the course of fourteen years on the air Futurama became a touchstone of modern animation that balanced heart and humor with some serious pathos.
Broad humor, self-deprecation, anachronism, slapstick and surrealism were all hallmarks of the show, and there was no situation that Fry, Leela, Bender and the gang couldn’t wring a laugh from.
15. Red Dwarf
Sci-fi comedy is always a delicate balancing act that many movies and TV shows have spectacularly pulled off, but few have got it anywhere near as right as Red Dwarf.
The first eight seasons aired between 1988 and 1999, but the show retained such a strong following that it was brought back a decade later for a further four runs and a TV movie that aired this year.
There’s been some major tonal shifts made over the years that have split opinion straight down the middle, but throughout it all the crew have remained as endearingly lovable as they’ve ever been.
14. The Outer Limits
The Outer Limits may have only been on the air for sixteen months and less than 50 episodes, but it still managed to leave a massive mark on sci-fi during the brief time it was on the airwaves.
The anthology series was of course heavily indebted to The Twilight Zone, but leaned much harder into the more outlandish realms of the genre than its more fantasy-based counterpart.
The 1995 revival ran for seven seasons but couldn’t quite recapture the magic of the original, which remains a landmark in sci-fi TV that went on to have a huge bearing on everything from Star Trek to The Terminator.
13. Orphan Black
Orphan Black wouldn’t have worked anywhere near as well as it did had it not been for Tatiana Maslany’s incredible work in the lead role, that saw her play half a dozen characters.
The narrative may have become increasingly convoluted during later seasons, but the leading lady could always be relied on to deliver, in what’s one of the most challenging and complex acting performances ever seen on the small screen.
The moral and ethical implications of human cloning have been a staple of the sci-fi genre for decades, but few shows have handled those themes with as much style or verve as Orphan Black.
12. Black Mirror
As an anthology series with a rotating cast of characters, actors and filmmakers, Black Mirror has inevitably been prone to inconsistency, but the very best episodes can genuinely be considered among the finest small screen works in recent memory.
The mind of creator Charlie Brooker clearly knows no bounds, and the show has only grown in popularity and found an even wider audience after becoming an international smash hit on Netflix.
Creative, shocking, difficult to watch, hilarious, prescient and so much more, often in the course of single episode, Black Mirror is the kind of unfiltered, singular and unique vision that very rarely makes to the screen without compromise.
11. The Mandalorian
The first live-action Star Wars show may only be ten episodes old, but creator Jon Favreau has already delivered the best thing to come out of the franchise’s Disney era by quite some distance.
Telling an all-new story set in a recognizable world is the ideal way to approach a mythology that’s become almost ubiquitous over the last four decades, and it also helps that the Baby Yoda phenomenon is along for the ride.
Influenced by everything from classic samurai movies to the golden age of the Western, The Mandalorian is a melting pot of genres that has won just as much acclaim from Star Wars fans as it has from viewers that were never interested in the brand before.
Firefly is the cult favorite to end all cult favorites, and the show’s existence can be summed up by the fact that when Joss Whedon was given the opportunity to continue the story on the big screen, Serenity promptly bombed at the box office.
A tongue in cheek space Western packed with charismatic actors and an endless barrage of quips, Firefly was destined to find a loyal fanbase from the second it first aired in September 2002, although it was swiftly canceled just fourteen episodes later.
Boundlessly imaginative and optimistic, Firefly distilled everything that had made Whedon a success in the first place into a frenetically-paced and richly detailed sci-fi series that didn’t stick around for anywhere near long enough.
9. Star Trek: The Next Generation
It was a fortunate stroke of luck that the follow-up to one of the most popular and beloved sci-fi shows ever made also went on to become one of the most popular and beloved sci-fi shows ever made, because when it first arrived Star Trek: The Next Generation had a lot to live up to.
The Next Generation continues to enjoy sustained popularity as every new generation of Trekkers discovers the show, which took everything that made the original series a success and made it bigger and bolder.
The Kirk vs. Picard debate will rage on until the end of time, as will the arguments between fans over which series is better. One thing everyone can agree on is that The Next Generation is top two material at the very least.
8. The Twilight Zone
The Twilight Zone has been brought back three times since 1964, most recently with Jordan Peele at the helm, but none of the revivals have been able to hold a candle to Rod Serling’s iconic original that would spawn 156 episodes.
As host, narrator, head writer and executive producer, the anthology series was a true labor of love for Serling, and made it clear that the multi-hyphenate was an incredible creative talent with imagination in endless supply.
Some of the most legendary moments in the history of television hail from The Twilight Zone, and the show’s influence over the sci-fi genre at large simply cannot be understated, and the monologues are still widely replicated and parodied to this day.
7. The Prisoner
The Prisoner ran for just a solitary season, but had enough of an impact on sci-fi that it has comfortably ascended into the pantheon of all-time greats, complete with the requisite cult following.
An intelligence agent is abducted and placed in a mysterious village, leading to all sorts of surrealist and existential adventures for Patrick McGoohan’s Number Six, with the leading man also co-creating, co-writing and directing several episodes of the series.
Despite the controversially open-ended conclusion, The Prisoner’s mix of espionage, sci-fi, allegorical themes, drama, psychological tangents and counterculturalism have seen its influence reach far and wide over the decades.
6. The Expanse
Syfy canceling The Expanse may turn out to be the best thing that ever happened to the ambitious sci-fi series, with the bumper Amazon budget making Season 4 the biggest and best yet.
Featuring some of the most well-rounded, developed and compelling characters to be found in any TV show regardless of genre, The Expanse’s political machinations are just as engaging as the intergalactic adventures.
Expertly crafted and rich in mythology, the series is as visually stunning as it is narratively gripping, and can easily be named as perhaps the single greatest sci-fi project currently found on the small screen.
5. The X-Files
Mulder and Scully became pop culture icons thanks to the overwhelming popularity of the X-Files, which was one of the biggest shows on TV throughout its initial nine-season run between 1993 and 2001.
The two feature film spinoffs and two revival seasons may have failed to hit the previous heights, but they nonetheless acted as solid additions to a canon that fans have been obsessing over for close to 30 years.
Driven by two charismatic and compelling leads that could sell even the most ridiculous plotlines and story contrivances with a straight face, The X-Files is entertaining genre TV of the highest order.
4. Star Trek: The Original Series
It seems hard to believe that the original run of Star Trek only lasted for three seasons given that it remains one of the most beloved shows in television history over 50 years after it was taken off the airwaves.
As well as launching several careers, a movie franchise and several small screen spinoffs, Star Trek’s influence on sci-fi at large is monumental, and history will always remember Gene Rodenberry’s creation as one of the genre’s monoliths.
It helps that the show itself was daring, groundbreaking, innovative, action-packed, humorous and frequently ingenious, resulting in an all-time classic that’s still a sci-fi touchstone with fingerprints all over modern interpretations of the standard tropes.
Netflix’s first German original series is also one of the best that the streaming service has ever produced, and tells one of the most complex stories ever told on the small screen, with even the tiniest throwaway moments ending up getting paid off one or two seasons down the line.
A child’s disappearance in a sleepy German town leads to the discovery of alternate universes, time travel and the intertwining fates of almost every resident, where even the smallest gesture can have a devastating impact later on.
The mythology is incredibly dense but never becomes impenetrable, and the weighty mediations on time and human nature are executed superbly as every single story thread in every one of the multiple timelines coalesces to form a hugely satisfying whole.
2. Battlestar Galactica
The third time was definitely the charm for Battlestar Galactica after the 1978 original and 1980 revival both failed to catch on, before the 2003 miniseries served as a successful backdoor pilot to what would soon become one of the greatest sci-fi shows in history.
The series delivered some of the richest subtext and allegory to be found on the small screen, reflecting modern day fears and issues in the guise of an enthralling intergalactic drama packed with big action and relatable characters.
Battlestar Galactica is a triumph whichever way you look at it, either through the lens of a sci-fi adventure, a political thriller, a suspense-fueled drama or just a fantastic work of television.
1. Doctor Who
Few TV shows in history have ever generated the same kind of fervent following as Doctor Who, which has admittedly suffered many ups and downs over the years, but the unwavering loyalty of the fanbase has never been in question.
With over 860 episodes and counting, Doctor Who offers no shortage of variety either, with both newbies and longtime Whovians having plenty of options to choose from when dipping into the extensive back catalogue.
No matter which incarnation of the titular hero the audience prefers, and that particular debate will never end, Doctor Who has inspired and influenced countless generations of filmmakers with Steven Spielberg, George Lucas, Tom Hanks, Edgar Wright, Tom Hanks, Robert Downey Jr., Johnny Depp all noted fans of the sci-fi classic.