Not all great best sci-fi TV shows of all time tend to hit the ground running, and even if they don't, they quickly grow into what they were intended to be and enjoy a multi-season run. However, some sci-fi shows crash and burn for reasons beyond their control, despite being well-thought-out and brilliantly executed.

I know it's unlikely that any of the shows on this list will ever get a second chance, but it doesn't hurt to dream. The genre is experiencing something of a renaissance at the moment, with platforms like sci-fi shows emerging recently makes me mourn some of my favorite failures within the genre.

Altered Carbon (2018-2020)

Netflix's cyberpunk epic deserved to continue

An adaptation of Richard K. Morgan's Takeshi Kovacs trilogy, Altered Carbon started very strongly with a faithful translation of the source material for season 1. Joel Kinnaman led the Altered Carbon season 1 cast as Takeshi Kovacs, telling the story of Morgan's 2002 trilogy-starter of the same name. Season 2 ittedly strayed from the books quite severely, but it remained engaging as Anthony Mackie replaced Kinnaman as the show's star.

Altered Carbon's premise offered the potential for a Doctor Who-style run that constantly refreshed the cast for canonical reasons. Although it largely turned its back on Morgan's work, I'm convinced Altered Carbon season 3 would have worked with a return to its roots of always keeping both eyes on the literary trilogy. I'd have loved to see more of Netflix's take on Morgan's sci-fi universe, and I'm still confused by the decision to end it so unceremoniously.

Constellation (2024)

Apple TV+ didn't give Constellation the chance it deserved to truly flourish

I didn't know what to expect when I first started watching Constellation, but I was pleasantly surprised by how much I enjoyed it. Beginning aboard a fictionalized (but realistic) version of the International Space Station, the Apple TV+ sci-fi thriller turned out to be a compelling take on the multiverse trope. Sure, alternate realities existed within the world of the show, but there were only two of them.

Constellation cast.

Terminator: The Sarah Connor Chronicles (2008-2009)

James Cameron's 2 Terminator movies immediately precede this sequel show

Even now, the Terminator franchise is still struggling to find a worthy successor to James Cameron's first two movies. The saga hasn't been quite the same since he stepped away. The Terminator timeline has been retconned so many times that it's difficult to keep up with what's part of the main canon and what isn't. The Sarah Connor Chronicles offers a brilliant alternative to those who don't vibe with any of the movies beyond 1991's Terminator 2: Judgment Day.

Ignoring the events of 2003's Terminator 3: Rise of the Machines, The Sarah Connor Chronicles served as a direct sequel to Judgment Day, and was a far better version of what happened after Cameron's era. It lacked the budget for the same level of special effects as its feature-length competitors, but the quality of the scripts and restoration of Cameron's original timeline made it easy to overlook any of the show's visual shortcomings. Unfortunately, Sarah Connor never got a proper ending. Despite an overwhelmingly positive reception, it was deemed unworthy of continuation after season 2.

Firefly (2002)

Mal Reynolds and his crew are still lauded as sci-fi legends despite a short run on TV

Firefly's confusing cancellation seems like an obvious topic to raise when discussing sci-fi shows ending before their time, but the fact that it has been over 20 years and everyone is still talking about it reinforces the fact that ending it was the wrong decision. A blend between sci-fi and Westerns, Firefly was a tricky show to market, which led to it not getting the expected viewing figures when it aired in 2002. Hybrid shows like this are commonplace in the modern day, but Firefly was something of a trailblazer in this respect.

Of course, Firefly has the advantage of not ending on a cliffhanger. Although the show itself ended without a satisfying resolution, the devoted fan base ultimately persuaded the higher-ups to give Nathan Fillion's Mal Reynolds and his crew the chance to say a proper farewell. In 2005, Serenity briefly revisited the Firefly universe for a feature-length adventure. Like Firefly, Serenity's performance didn't match its quality. However, it remains a great part of the saga, and could probably have kick-started a Firefly revival with enough effort.

Star Wars: The Acolyte (2024)

The franchise's live-action High Republic era was far better than disgruntled fans made it out to be

In true Star Wars fashion, The Acolyte failed to hit home with its fan base despite boasting many of the elements that have proved successful in the past. An extension of the Star Wars: High Republic book series, The Acolyte was an attempt to acknowledge the canonical source material while also making that era of the Star Wars timeline accessible to newcomers. The Jedi-heavy storyline was slickly shot, and felt authentic to the Star Wars universe while also offering something fresh.

Despite Star Wars prequel movies. A key Dark Side figure was on the cusp of entering the fray, but apparently, that wasn't good enough.

Terra Nova (2011)

This mashup of Lost & Jurassic Park really felt like it was headed somewhere

Initially set in a dystopian 22nd century and executive produced by Steven Spielberg, Terra Nova tells the story of a family fleeing an incredibly polluted Earth and heading back to the planet's Cretaceous period to live in a human colony while dinosaurs roamed around. It sounds like an idyllic and creative solution to the death of the human homeworld, but Terra Nova's lone season is full of unexpected twists and turns.

Spielberg's input is evident in Terra Nova's cinematic camerawork and high-stakes storyline, while remaining fairly accessible to those who don't often engage with sci-fi. I don't think there has been another show like Terra Nova since, which makes it all the more disappointing that it was canceled so quickly. Still, it ticks several sci-fi hallmarks and is still work checking out, even with an incomplete arc.

Source: Rotten Tomatoes