Unmissable Free Sci-Fi Streaming: Top 10 Shows to Binge-Watch Now

Thankfully, there are numerous free streaming services, albeit ad-supported, such as Pluto TV, Tubi, and Plex. These platforms boast an impressive collection of sci-fi TV series, including some of the genre’s classics. We’ve compiled a list of the ten finest sci-fi shows currently available on these free services, complete with direct links to start watching instantly.

Creators: René Echevarria, Scott Peters
Cast: Joel Gretsch, Jacqueline McKenzie, Mahershala Ali
Years Aired: 2004-2007
Watch for Free on: Tubi

Renowned as one of the top-rated sci-fi series of the 21st century, “The 4400” also stands out as a premier time-travel narrative. Its brilliance lies in the way it handles themes like alien phenomena, time manipulation, and supernatural powers, keeping most of these elements intriguingly ambiguous and thought-provoking.

“The 4400” centers on a galactic event that seems to have brought back the titular number of people who had gone missing within the last half century. Not only that, but many of them now have superpowers and are revealed to be violent and dangerous. This leads to the creation of a government agency tasked with keeping tabs on them.

Not only is “The 4400” one of the best-reviewed sci-fi shows of the 21st century so far, it’s one of the best time-travel shows of all time, period. One of its greatest strengths is that, despite a premise that includes alien comets, time travel, and magical abilities, “The 4400” smartly keeps most of its more fantastical elements in the realm of the abstract.

The action here remains fairly grounded and character-driven throughout, and the impressive cast — including an early role for future two-time Oscar winner Mahershala Ali — really makes that approach sing. There was a 2021 reboot on The CW titled simply “4400” that was actually pretty good, but it was canceled after one season and isn’t currently available to stream free anywhere. 

Creator: Chris Carter
Cast: David Duchovny, Gillian Anderson, Robert Patrick
Years aired: 1993-2002, 2016-2018
Streaming free on: Pluto TV

The 1990s saw something of a sci-fi TV renaissance. In particular, more serious and less intentionally campy sci-fi, the latter of which encompassed much of the genre on the small screen throughout the ’70s and ’80s. Perhaps the most grounded hit sci-fi show from the ’90s was Fox’s “The X-Files,” which also leaned heavily into another major pop culture touchstone of the decade: conspiracy theories about aliens and supernatural phenomena.

The main dynamic that drives “The X-Files” is the relationship between its two FBI agent leads: Fox Mulder (David Duchovny) and Dana Scully (Gillian Anderson). Mulder not only believes in all the wild stuff they are investigating, but actively wants to believe in it. Scully, on the other hand, is the skeptic who presumes everything has a rational, non-fantastical explanation — a cynicism she continues to stubbornly hold onto despite all the otherworldly things she sees alongside Mulder.

While all of the best “X-Files” episodes fall within the show’s original run, the two not-especially-beloved 2010s revival seasons are also available to stream free for the completionists out there.

Creators: Sydney Newman, C.E. Webber, Donald Wilson
Cast: Tom Baker, Jon Pertwee, Sylvester McCoy
Years aired: 1963-1989
Streaming free on: Pluto TV

To get this out of the way right up front, we aren’t talking about the run of “Doctor Who” that began in 2005 — the era that is generally referred to as “modern Doctor Who” or “NuWho.” This is about the original, classic run of “Doctor Who” that lasted for an impressive 26 seasons between 1963 and 1989. If you’ve only seen the newer seasons, then stop sleeping on classic “Who,” because it’s just as entertaining. As a matter of fact, in Looper’s ranking of the doctors from worst to best, we put Tom Baker (Season 12 to Season 18) as the portrayer of the all-time greatest version of the title character.

Sure, a lot of classic “Doctor Who” is very campy and goofy, sometimes intentionally so and sometimes not so much. But it also ages a lot better than you might think. We’d recommend starting with the Tom Baker years and then working your way back through the seasons from there for as long as your tolerance for the datedness of the costumes, effects, and overall visual quality can sustain. Just note that the complete 26 season run of classic “Doctor Who” isn’t available on Pluto or anywhere else for that matter: Sadly, 97 episodes are considered lost forever due to the BBC’s poor archiving practices at the time.

Creator: Simon Barry
Cast: Rachel Nichols, Victor Webster, Stephen Lobo
Years aired: 2012-2015
Streaming free on: Pluto TV

Another sci-fi show with a heavy emphasis on time travel, “Continuum” sees a group of terrorists from 60 years in the future escape their impending death sentences by hiding out in 2012. One of the law enforcement officers pursuing them — Kiera Cameron (Rachel Nichols) — accidentally comes to 2012 with them. Kiera must hunt them down while also figuring out a way to get back to her family in her own present.

While it’s probably the least-known show on this list (especially if you don’t live in Canada), “Continuum” is no less worthy of your attention. Debuting on the Canadian network Showcase in May 2012, the series came to Syfy in the United States in June 2013. For each of the subsequent three seasons, the gap between the Canadian and U.S. airings became much shorter. All four seasons are now streaming for free on Pluto TV. 

“Continuum” was initially canceled before it had a chance to wrap up its story, but, thankfully, the writers were subsequently granted six more episodes with which to bring things to a proper conclusion, so Season 4 is shorter than the others. There are plenty of sci-fi shows that ended on cliffhangers that will never be resolved, but this isn’t one of them.

Creator: Gene Roddenberry
Cast: Patrick Stewart, Jonathan Frakes, LeVar Burton
Years aired: 1987-1994
Streaming free on: Pluto TV

Full disclosure — “Star Trek: The Original Series,” “Star Trek: The Next Generation,” “Star Trek: Deep Space Nine, “Star Trek: Voyager,” and “Star Trek: Enterprise” are all currently available to stream on Pluto TV. So you’ve got tons of free “Star Trek” available to you that will keep you plenty busy even without having to subscribe to Paramount+. But the general consensus among Trekkies is that “The Next Generation” is the best “Star Trek” series of all time, so if you only watch one — or just need a recommendation of where to start — “TNG” is the way to go.

Initially divisive among “Star Trek” fans, many of whom weren’t willing to accept a whole new crew after so many years, “TNG” had a rough start as it found its creative footing. But from Season 2 onward, audiences fell in love with Picard (Patrick Stewart), Riker (Jonathan Frakes), Data (Brent Spiner), Worf (Michael Dorn), Geordi (LeVar Burton), and the rest of the “TNG” crew. 

People also came to appreciate that “TNG” wasn’t just a carbon copy of the original series and brought an entirely different — and much less campy — vibe to the franchise. The show also introduced new fan favorite villains like the Borg and Q (John de Lancie), while seeing former big bads the Klingons become not only allies but Enterprise crew members in some cases.

Creators: José Rivera, Karl Schaefer
Cast: Omri Katz, Justin Shenkarow, Mary-Margaret Humes
Years aired: 1991-1993
Streaming free on: Plex

While not everyone is convinced that the changeover from traditional television to a streaming-focused world has been an overall net positive, there are a few aspects of streaming that have proven to be undeniable benefits. Case in point, a show like “Eerie, Indiana” becoming not only readily available but even free to stream on Plex after having spent many years only being available to watch via an expensive DVD box set. It initially aired for just one season on NBC, becoming a cult classic via syndicated cable reruns before eventually falling off the programming blocks and becoming incredibly difficult to watch.

The simplest way to describe “Eerie, Indiana” is that it has the surreal vibe and humor of “Twin Peaks” and the sci-fi-stories-with-a-twist conceit of “The Twilight Zone.” It’s set in the titular town, a place that seems to be the epicenter of all manner of supernatural and extraterrestrial weirdness. The even lesser-known single-season 1998 spin-off “Eerie, Indiana: The Other Dimension” is also currently streaming on Plex. It is inferior to the original but is still a fun watch for fans. 

Should you watch both seasons of the “Eerie, Indiana” franchise and want even more of that type of vibe, the excellent Disney animated series “Gravity Falls” (which contains a lot of things that only adults notice), is not only very reminiscent of the show but was directly inspired by it. Of course, you’ll need Disney+ for that one. 

Creators: Brad Wright, Jonathan Glassner
Cast: Richard Dean Anderson, Michael Shanks, Amanda Tapping
Years aired: 1997-2007
Streaming free on: Pluto TV

One of the most fascinating journeys of a sci-fi franchise has been that of “Stargate.” Initially a somewhat entertaining but ultimately forgettable 1994 film, that should’ve been the last we heard from “Stargate” with the possible exception of a few slapdash direct-to-video sequels. Yet, it became a huge multimedia franchise with several TV shows, a whole series of novels, and multiple comic book lines. However, that didn’t all happen because of the movie. Instead, it was the result of both the popularity and the shockingly high quality of the first TV show in the franchise, “Stargate SG-1.”

Though it picks up a year after the ending of the movie, watching the film isn’t required to start up and follow along with the show. All you need to know is that SG-1 is one of a number of military outfits that Earth sent out into the universe via the Stargate portal, searching for alien technology and allies to help fortify humanity’s defenses against various intergalactic foes.

“Stargate SG-1” initially premiered on Showtime, which might seem like an odd fit. However, the show’s producers have admitted that it wouldn’t have initially pulled in the viewer numbers to have gotten renewed had it been on a traditional network. Showtime allowed “SG-1” to find its audience across five seasons, and when it was canceled, Syfy picked it up and made an additional five seasons, with the series becoming its highest-rated original show in the process.

Creators: Michael Piller, Shawn Piller
Cast: Anthony Michael Hall, Nicole de Boer, John L. Adams
Years aired: 2002-2007
Streaming free on: Pluto TV, Tubi

When considering every Stephen King TV series ranked worst to best, USA Network’s “The Dead Zone” finishes near the top — particularly if you take out miniseries and only consider traditional shows. The second adaptation of King’s 1979 novel of the same name after the 1983 film, the TV series was a big enough hit that it got an impressive six seasons between 2002 and 2007. Unfortunately, it ended on a cliffhanger after talks of Syfy picking it up for one last season didn’t pan out — but don’t let that stop you from checking out one of the breezier and more fun adaptations of a King story. 

Anthony Michael Hall plays Johnny Smith, who spends six years in a coma after a car accident. When he wakes up, he finds that he’s gained the ability to see visions by touching people — sometimes of past events, and sometimes of the future. He decides to use his power to solve crimes in his town, but he soon suspects that he’s meant for a larger purpose when his visions begin to include that of an apparent impending world-ending catastrophe. “The Dead Zone” is an underrated Stephen King adaptation, and it saved Anthony Michael Hall’s career.

Creator: Rockne S. O’Bannon
Cast: Ben Browder, Claudia Black, Virginia Hey
Years aired: 1999-2003
Streaming free on: Plex

Rockne S. O’Bannon isn’t exactly a household name, but he’s well known in certain sci-fi circles. His early writing credits include the ’80s reboot of “The Twilight Zone” and the Steven Spielberg anthology series “Amazing Stories,” and he went on to create the shows “Alien Nation” (based on his film of the same name) and “SeaQuest DSV.” But his defining project, and the one with which he definitely deserves his spot in the sci-fi TV pantheon, is “Farscape,” the 1999-2003 series that he created and wrote multiple episodes of.

Those who only ever just saw the commercials for “Farscape” could be forgiven for lumping it in with the many forgettable “Star Trek” rip offs of the ’90s. But that does a disservice to the show, as it is anything but that. It centers primarily on a diverse group consisting of various intergalactic species who reside on a living ship that is trying to stay out from under a corrupt military regime. With costumes, prosthetics, and puppetry by the Jim Henson Creature Shop, “Farscape” stood out from sci-fi shows of the era by having more elaborate alien designs that weren’t just human actors with painted skin and only slightly exaggerated features. 

O’Bannon has been kicking around the idea of a film revival of “Farscape” since 2013, with Brian Henson also frequently weighing in to reaffirm his interest in continuing the franchise. However, this has yet to happen — the 2005 miniseries “Farscape: The Peacekeeper Wars,” which was made to wrap up some loose ends from the original show, remains the most recent entry. The franchise is crying out for a modern reboot, but the original series is still very much worth your time.

Creator: Rod Serling
Cast: Rod Serling, Robert McCord, Jay Overholts
Years aired: 1959-1964
Streaming free on: Tubi, Pluto TV

“The Twilight Zone” is one of the most rewatchable sci-fi shows of all time. The number of trails blazed by the famous anthology series is a list unto itself. It laid the foundation for modern science fiction television, modern anthology shows, and so much more. Its creator and presenter, Rod Serling, was also impressively ahead of his time in terms of openly challenging censorship, racism, prejudice, and many other issues that few people were willing to even discuss in the ’60s, let alone be outspoken about.

The most famous element of “The Twilight Zone” is its tendency to effortlessly insert some sort of social lesson within the confines of a sci-fi story, with many episodes of the show famously ending with a twist that you never saw coming. That reading does oversimplify “The Twilight Zone” a bit, as not every episode follows that formula and many get much more creative than that. But there’s a reason why people still not only talk about it, but watch it over 60 years later. If you’re interested in getting into it but don’t know where to start, check out Looper’s ranking of the 30 best episodes of “The Twilight Zone.”