With the abundance of exciting sci-fi TV shows available to viewers, it's not surprising that some of them can slip under the radar. As a result, the viewing numbers don't meet the executives' expectations, and even the most excellent and promising series get canceled before their time.

While some sci-fi shows like Heroes, The X-files, and Haven arguably overstayed their welcome, other, less-known gems never got a chance to shine and reveal their full potential. Even though these 5 underappreciated sci-fi series got canceled after only one season, they well deserve the time and attention of any genre fan.

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Terra Nova (2011-2012)

Terra Nova got canceled after only one season

Fox Network is notorious for its often bewildering cancellation decisions, especially when it comes to sci-fi and fantasy shows. This Jurassic Park-style adventure, which features a superb cast that includes Jason O'Mara, Christine Adams, and Stephen Lang and boasts Steven Spielberg as executive producer, fell yet another victim to the unfortunate trend. The story follows the Shannon family that fled the overpopulated and polluted 2149 Earth through a temporal rift to the Cretaceous Period, unspoiled but brimming with all the associated dangers. Together with other 'pilgrims,' they join the Terra Nova colony and face a group of separatists, known as the 'sixers,' who aim to profit from smuggling the pre-historic resources to 2149, despite dire consequences for the environment and Earth's future.

Terra Nova is intriguing, suspenseful, and exceptionally well made, which is reflected in several awards. It has a great premise, distinct character development, and an intriguing twist at the end of the first season. Even though the audience is left with a cliffhanger, the available 13 episodes are still worth watching.

Flashforward (2009-2010)

Flashforward got canceled after one season

This excellent ABC sci-fi drama came out on the heels of Lost, with the studio hoping for similar success. The premise is intriguing and promising — almost everyone on Earth blacks out for 137 seconds and sees a glimpse six months into their future. The story focuses on an FBI task force, led by Mark Benford (Joseph Fiennes), who investigates the reasons and implications of the blackout, as well as those who were mysteriously exempt from it. While the show's crime aspect keeps the audience in suspense, the characters' personal drama, deliberations, and attempts to understand, deter, or accelerate their respective futures make Flashforward unique and intensely emotional.

The series had an unfortunate combination of declining ratings, an extended hiatus, and the loss of multiple showrunners, which led to its eventual cancelation. However, the fans were not ready to let it go and launched a 'Save Flashforward' campaign, with signed petitions, social media campaigns, and even staged 'blackouts' in front of ABC offices. If nothing else, this devotion is a sure sign that this underrated show deserves a watch.

Awake (2012)

Jason Isaacs in Awake

The combination of Mind Games and Fear Street: Part One - 1994's Kyle Killen as the show's creator and Harry Potter's Lucius Malfoy, Jason Isaacs, as the lead actor are enough to mark the series as promising. Awake tops it up with an original premise — an LAPD detective Michael Britten gets into a horrific car crash with his wife and son and starts switching between two grim realities in his sleep; in one, he and his wife have to deal with the loss of their son, and in the other, he has to bring up his son as a single parent after the death of his wife. If that wasn't enough, Britten also picks up clues from each reality to solve cases in the other, all the while wondering which of them is real. The emotional story, sprinkled with some elements of procedural crime drama, Isaacs' superb and nuanced performance, and a dizzyingly dynamic pace all make for a nail-biting and compelling watch.

Awake's first and only season ended with a big revelation. Even though it would have been undoubtedly interesting to see where the story goes from there, at the very least, the conclusion of this underrated sci-fi series gives a much-needed sense of closure.

Almost Human (2013-2014)

Karl Urban and the rest of the cast of Almost Human

Another victim of Fox's puzzling cancelation wave, J.J. Adams' future-set Almost Human featured the modern sci-fi star (Lord of the Rings, Star Trek, Dredd, and The Boys make for one impressive portfolio), Karl Urban, as a troubled detective John Kennex, who has a good reason to resent androids but is eventually partnered with one. The evolving robot-human relationship and a growing bond become the show's centerpiece, lend it a ton of heart, and allow the audience to enjoy an entertaining dynamic. The show's wise decision to depict a realistic rather than wildly imaginative future, the android's dry wit and reluctance to be associated with any implications of the term 'synthetic,' Kennex's investigation into his sustained blackout and lost memories about a sinister syndicate, and their crime-fighting endeavors make Almost Human a thoroughly enjoyable viewing experience.

Unfortunately for the show, its episodes were inexplicably aired out of order, confusing the audience and leading to an understandable decline in viewing numbers. Even though Almost Humanwas canceled after only one season, the existing 13 episodes shouldn't be missed.

Firefly (2002-2003)

Firefly series cast and Captain Mel Reynolds (Nathan Fillion)

Written and directed by Joss Whedon, this fantastic and brilliantly original sci-fi/western follows a raggedy group of space smugglers under the command of charismatic Captain Mal Reynolds (Nathan Fillion) as they take on the most bizarre contracts, all the while trying to fly under the radar of the Alliance federal government. The show suffered the same fate as Almost Human, with its episodes aired out of order by Fox that also gave it an infamous Friday night 'death' slot. Despite its eventual hasty cancelation (which is widely considered to be one of the most inexplicable and regrettable decisions in the history of sci-fi shows), Firefly gained a cult following and an ever-growing army of 'Browncoats' and 'Firebronies,' who are still hoping for the series' revival. What's more, the show's popularity prompted the release of the 2005 sequel movie Serenity, as well as an ongoing comic book series.

Firefly's unique setting, irreverent humor, an abundance of outright-quotable lines, diverse and fleshed-out characters, and a superb cast with sparkling chemistry that includes Gina Torres, Alan Tudyk, and Adam Baldwin make it one of the best shows canceled after only one season and an absolute must-watch for any sci-fi fan.

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