6 Best Long-Running Sci-Fi TV Series to Binge-Watch

There have been some fantastic sci-fi TV shows over the years, but only a few have managed to last for more than five seasons. The list of the best sci-fi shows ever includes a lot of series that only ran for a handful of seasons. It just gets hard to maintain quality the longer a show goes on.

These six series prove, however, that a science fiction show can last for many years and still be strong all the way through. Not every single season of these shows is great, but enough of them are that we can call the show great. These are the sci-fi shows to watch when you want something to last you months.

Stargate SG-1 (1997-2007)

10 Seasons

Stargate SG-1 is a military science fiction adventure set within the universe of the 1994 film Stargate. Picking up a year after the events of the movie, the series follows the Earth-trained military team called “SG-1”, a secret organization that travels through these wormhole-like stargates to search for alien technology to protect the Earth.

The series draws upon ancient myths and legends, providing backstory about the history of the world. Along with other SG teams, SG-1 finds enemies and allies across the stars. While the lore of Stargate SG-1 is extensive, it’s the relationships between the crew members that make it so watchable.

Unlike similar sci-fi shows of the time, Stargate SG-1 made an effort not to take itself too seriously, often referencing current pop culture and planting its tongue in its cheek. The series was slow to take off, but over the seasons, it kept improving and is now beloved for its approachable, easy-going sci-fi attitude.

Star Trek: Deep Space Nine (1993-1999)

7 Seasons

Image by Yeider Chacon

Star Trek: Deep Space Nine ran for seven seasons between 1993 and 1999 and is generally ranked among the best Star Trek series. Unlike previous shows, DSN is set on a space station, the eponymous Deep Space Nine, rather than a spaceship. It’s also the first to have an African American actor in the lead role.

Starfleet Captain Benjamin Sisko (Avery Brooks) helms a space station that includes both Starfleet members and Bajorans, the native inhabitants of the nearby planet, Bajor. When a wormhole appears near the planet, Deep Space Nine becomes the crux of exploration, trade, and political movement in the galaxy.

DSN drew a lot of praise for its inclusion of more minority characters than had ever appeared on Star Trek and for its more morally ambiguous slant. Unlike the strapping heroes of previous installments, the characters in DSN were not always in the right, providing interesting philosophical quandaries as the series went on.

Doctor Who (1963-Present)

41 Seasons

Doctor Who is one of the longest-running TV shows of all time. It began in 1963, and it’s gone on steadily into the present with only a handful of years gone by without the time-traveling Doctor on TV. Since the premiere, there have been five Doctors, played by a variety of different sorts of actors.

The extraterrestrial being called the Doctor is a reincarnating being known as a Time Lord, a rogue one at that. The Doctor travels through time and space, often with a couple of companions, investigating curious happenings and preventing evil wherever they can. Originally a children’s show, Doctor Who has acquired fans from all generations.

Imaginative, funny, daffy, charming, and occasionally frightening, Doctor Who is a lot of things to a lot of people. Even with nearly 900 episodes, there are still some people who haven’t seen the series. Yet it remains a crucial piece of pop culture. Even if you don’t know Doctor Who, you’ll recognize its influence everywhere.

The X-Files (1993-2018)

11 Seasons

The X-Files has transcended simple science fiction television and is arguably one of the most influential pieces of media of the last 35 years. The series stars David Duchovny and Gillian Anderson as FBI Special Agents Fox Mulder and Dana Scully, respectively. The pair is responsible for investigating a unique kind of crime.

The cases they investigate are of the paranormal kind. Anytime there’s a whiff of the supernatural, extraterrestrial, or inexplicable, Mulder and Scully are there. Over the course of eleven seasons, two of which came 15 years after season 9, the pair uncover mysteries and develop a tentative romance.

While the monsters and creatures are amazing, it’s the investigations and storytelling that really make The X-Files such an important show. It’s a deceptively clever series, not necessarily with the science, which can be wonky, but with the writing and characterizations that always feel honest and authentic.

Star Trek: The Next Generation (1987-1994)

7 Seasons

It’s a toss-up for Star Trek fans about whether Star Trek: The Next Generation or Deep Space Nine is the better series. While both have their arguments, TNG takes the crown primarily because of how much it influences what has come after it. The TNG cast alone is one of the franchise’s most memorable.

The third series in the franchise, TNG follows the crew of the USS Enterprise, a Starfleet ship helmed by Patrick Stewart as Jean-Luc Picard. He’s joined on his many adventures by Data (Brent Spiner), Worf (Michael Dorn), Geordie La Forge (LeVar Burton), Deanna Troi (Maria Sirtis), and a handful of others.

Set a century after the events of the original series, TNG felt a bit grander than the original show. Stories often required multiple episodes to tell and often dug into deep philosophical questions. Without TNG, the Star Trek series would not be where it is today as one of the most important sci-fi franchises ever.

The Expanse (2015-2022)

6 Seasons

The Expanse is one of the best sci-fi TV shows to ever air, and with six seasons, there’s plenty of action, drama, and philosophical questions for those interested in a new show. Based on James S. A. Corey’s novels of the same name, The Expanse is set in a future where humans have conquered most of the Solar System.

Since this expansion, three large empires have grown to dominate. A disparate band of protagonists comes together on board the Rocinante spaceship and unwittingly makes a discovery that threatens the fragile peace between the largest powers around.

Extremely technically and scientifically accurate, The Expanse works hard to ensure the logic of its story is airtight. However, that doesn’t mean the show doesn’t care about plot and characterization. The Expanse is an intriguing and even noirish sci-fi with a lot of relevance to today’s world political climate.