5 Sci-Fi Shows With No Bad Episodes

Science fiction has long been a source for excellent television programming, going back to the the 1950s with the first pre-recorded sci-fi series, "Rocky Jones, Space Ranger." Since then, the genre has exploded in popularity and racked up all kinds of hit series, from "Lost in Space" and "Star Trek" in the 1960s to "Rick and Morty" and "Stranger Things" in the 2010s. 

For the most part, however, even the best sci-fi shows have a handful of bad episodes that fail to entertain the fans, whether it's in a long-running program like "Doctor Who" or a miniseries like "Black Mirror." Whatever the reason, it's fairly common, as it's incredibly difficult to consistently produce top-tier entertainment on a weekly or even yearly basis without stumbling once or twice.

A science fiction series that has absolutely no bad episodes is far less common, and throughout the history of the genre, only a handful of series can make such a claim. It's not even common outside of sci-fi, making any series of any kind without any misfires something of a unicorn. Still, there are a few excellent science fiction shows that have produced no duds at all, according to critics and viewers. Each of these five sci-fi shows — arranged in chronological order of release — arrived on our television sets and pumped out nothing but quality episodes, one after the other.

The original "Battlestar Galactica" premiered in 1978, but only lasted a single season. A year later, "Galactica 1980" attempted a reboot, but it too failed to find a footing. Then, in 2003, showrunner Ronald D. Moore reimagined the original premise and produced a three-hour "Battlestar Galactica" miniseries. This time the miniseries landed positively with viewers and critics, earning Moore a green light to produce a new show.

"Battlestar Galactica" spans an extensive timeline, beginning 40 years after the war with the Cylons, though it doesn't take long for a new one to begin, starting with the nuclear annihilation of the Twelve Colonies. The series centers around its titular starship, the military members onboard, and a large flotilla of civilian spacecraft consisting of around 50,000 survivors. They flee from the Cylons in search of Earth, but they're constantly pursued by the relentless killing machines, some of which look like humans and have infiltrated the survivors' fleet.

"Battlestar Galactica" was a huge hit for what was then known as the Sci-Fi Channel (now Syfy), running for 76 episodes over four seasons plus two made-for-TV movies. There was also a web series and a spinoff, with the property permeating popular culture thanks to its excellent acting, writing, and use of a limited budget, which made the show seem more realistic. "Battlestar Galactica" holds a series rating of 95% on Rotten Tomatoes— and none of its episodes are bad.

Famed comic book scribe Robert Kirkman's coming-of-age superhero story, "Invincible," was first published in 2003 and ran for 144 issues before concluding in 2018. While not as famous as Kirkman's other hit, "The Walking Dead," "Invincible" retained a huge fanbase that continued purchasing the trade paperbacks for years. Although a live-action film was greenlit, the animated series beat it to production, premiering in 2021 with "The Walking Dead" alum Steven Yeun voicing the titular superhero.

"Invincible" streamed on Prime Video to amazing success, locking in new fans who'd never heard of the comics while pleasing the ones who had read every book since the beginning. That's not an easy thing to do, but the series has closely mirrored the story in the comics from the start. Given how bloody and violent the books are, it wouldn't have been outside the realm of possibility for an animated adaptation to tone it down. Fortunately, that didn't happen, and the animated "Invincible" is arguably even more violent than its comic book counterpart.

On top of that, "Invincible" features an extraordinary cast, each of whom brings their characters to life as if they were written specifically for them. As of this writing, "Invincible" has aired four seasons, with more to come. While it's possible that a forthcoming episode might not be up to the standards set thus far, that seems unlikely. Every episode has been brilliantly acted, beautifully animated, and excellently written, earning the series a 99% on Rotten Tomatoes.

On the surface, the premise of "Severance" sounds enticing: who wouldn't want to split their work memories from their personal and social life, effectively bisecting oneself into two people? But "Severance" is so much more than a simple division of memories, as each person who undergoes severance effectively does become two distinct people, one of whom gets to enjoy life as they see fit while the other knows nothing but the four walls of the office and the small group of people there.

On top of the moral ambiguity of dividing a person's personality in such a way, "Severance" turns the creep factor so far beyond 11 that the dial breaks. Every scene in each episode meticulously crafts a palpable tension that drives the overall series theme of identity. Almost nothing within Lumon Industries makes sense, which only increases the anxiety the audience feels while watching it. Few shows come anywhere close to the utter brilliance that is the writing of "Severance."

Not only do the characters not know what's going on in their own lives, but "Severance" has been playing mind games on the audience from the very beginning. Each prop or hallway is designed to mess with viewers' heads. Yet the series is also relatable despite its sci-fi approach to memory manipulation, and while a third season is in the works at press time, the first two seasons contain no bad episodes. Overall, "Severance" holds a 95% rating on Rotten Tomatoes.

The "Star Wars" franchise has been pumping out content ever since Disney bought Lucasfilm, not all of which fans have enjoyed. To be fair, the fandom is one of the most toxic and has lambasted Disney's decisions since the purchase. Despite this, Disney hasn't stopped producing films and television series  in the "Star Wars" universe, the best of which is "Andor." Although "The Mandalorian" might arguably hold that distinction, only one of the two has no bad episodes.

"Andor" consists of a detailed timeline of the life of Cassian Andor (Diego Luna), first introduced in "Rogue One: A Star Wars Story." The first season depicts Andor in his pre-Rebel days, selling stolen Imperial technology to make a living. After he's attacked by two security officers that he kills, Andor becomes the Empire's No. 1 target in the sector. What follows is a massive heist, Andor's arrest and incarceration, jailbreak, and his decision to join the growing Rebellion.

Season 2 picks up after the events of the first, and is broken up into four parts, each consisting of three episodes that cover one year. The series concludes with Andor leaving with K-2SO (Alan Tudyk) to fly to Kafrene, where he's next seen in the opening act of "Rogue One." The series is absolutely perfect in its depiction of Andor as a rogue-turned-rebel, and every one of its episodes is unique to the overall story. "Andor" maintains a rating of 96% on Rotten Tomatoes.

The "Fallout" video game franchise began in 1997, introducing the world to Interplay's unique take on a nuclear apocalypse. Over the years, the franchise expanded, building up a mountain of lore that details an extensive history across several centuries. For decades, "Fallout" was primarily limited to games, but after Amazon purchased the rights in 2020, that changed. Todd Howard, the director and producer of several of the games, signed on to executive produce, and the live-action adaptation premiered in December 2025.

"Fallout" absolutely blew everyone away with its meticulous attention to detail in presenting the video game world as a television series. Every broken car, each destroyed building, and all the irradiated food you can eat harkens back to the games. The same is true of many of the characters and locations. In this way, "Fallout" has been a rousing success with fans of the games, but they're not the only ones watching the series, as it's incredibly popular.

Still, loyalty to the lore is incredibly important, and "Fallout" hasn't failed in this by any measure. Each episode continues the overall narrative surrounding Lucy (Ella Purnell), The Ghoul (Walton Goggins), Maximus (Aaron Moten), and the rest of the characters. It all coalesces into an outstanding adaptation that consistently pushes out one amazing episode after the other, without a single one being poorly received. "Fallout" has aired two seasons as of this writing, with another one on the way from a show that holds a rating of 94% on Rotten Tomatoes.