Sudden cancellations and unresolved cliffhangers are bummers for any fans. However, sci-fi fans seem to have to deal with it more than others. There are so many infamous science fiction shows canceled “before their prime” that people have made tons of lists on them. Yes, we already hear the people in the back yelling “Firefly”. It’s only an added salt in the wound when that canceling comes with a really juicy cliffhanger that fans never get to see resolved.

Dark Matter

Creators planned for Dark Matter to last five seasons, following the adventures of the amnesiac, lovable crew of the starship Raza. However, as one of the most expensive Syfy shows to make, it was cut short after three seasons.

The sudden stop was particularly heartbreaking because the series left on a brutal cliffhanger: the galaxy is being invaded by mind-corrupting aliens and Six flies a ship into imminent danger to try to blow up their entry point—and then cuts to black. Fans were doomed to never find out, but luckily one of the show’s creators, Joseph Mallozzi, has done his best to fill fans in on what would have happened despite the cancellation.

Firefly

No one can ever make a list about disappointing endings or cliffhangers without mentioning Firefly. A sci-fi fan darling, the series was cut after a single season. Executives cited ratings and expense problems, but it doesn’t break fans’ hearts any less.

While the final episode itself isn’t a classic cliffhanger, the series is. The season left so much open and unexplained, between the horrifying Reavers, River’s powers, the unresolved relationships between all the crew-members, and more. Though the series got a movie, Serenity, to try to cover all those loose ends, it was impossible. There was too much to cover cohesively and the film just ended up a hollow token after losing such a promising story.

Sliders

Unlike many shows listed here, Sliders wasn’t cut off before its prime. The show lasted an impressive five seasons before getting the ax. However, it’s ending wasn’t any less devastating for fans. The series built up this big, action-packed, dramatic finale with one serious cliffhanger. The sliders were on an alternate earth, but there was chaos and destruction happening on Earth-Prime. Rembrandt injected himself with a humanity-saving serum and sent himself through the vortex. He said Mark would be able to use his own seeing powers to tell them what happened.

Unfortunately, after he slid, Mark had a heart attack and passed on. Fans don’t know what happened to Rembrandt, Earth-Prime, or if his friends ever went after him.

V (both times)

V is the story of human-skin wearing lizard aliens that come to Earth. At first, these “visitors” are super helpful, curing diseases, falling in love with locals. However, ultimately their goal is world domination. This sci-fi story has ended up on TV screens twice, and both times the series ended on a cliffhanger. In the 80s, the show ended on the humans sending out a beacon for help, hoping another alien species would come help them. Fans never would know if that would work or, more terribly interesting, what kind of aliens would come help them.

In the 2009 series, the show ended with its second season. Anna, the leaders of the visitors, finally discovered a way to mind-control most everyone on the planet. Smugly, she assumes she’s won, and the few heroes left are practically helpless in comparison to a planet of puppets. Yet again, fans never would learn how humanity survived that cliffhanger.

Quantum Leap

Trekkies might know Scott Bakula as Captain Archer of the Enterprise, but even older sci-fi fanatics know him as Sam Beckett, the scientist falling through time. For five seasons, Sam bounced around from time to time, trying to find his way back home. Unlike a lot of the other shows, though, Quantum Leap knew it was getting canceled so at least made an attempt at an ending (albeit a bizarre, confusing one).

In the end, Sam travels to his own date of birth and gets told by a stranger that he always had control over time travel (Dorothy Gale style) and should help the universe. Sam seems satisfied with that and keeps on traveling.

Not only are fans left hanging with no real conclusion to Sam’s journey, but also, it doesn’t make sense for Sam to not want to go home by then.

The Sarah Connor Chronicles

Terminator and Terminator 2 have always been sci-fi darlings, but past that most adaptations of the classic have not done well. That is, excluding The Sarah Connor Chronicles. This Syfy series is looked fondly upon by sci-fi fans despite being cut short after its second season, and, boy, what a second season finale that was.

After some misunderstanding hijinks, John Connor ends up thrust into the future where he meets the future heroes and his own father, Kyle Reese. However, no one there knows him, his mom and Cameron aren’t there to help him, and the trajectory of the resistance has changed completely. Sounds like it would have led to some interesting storytelling if it didn’t end, huh?

The Dead Zone

The Dead Zone was a TV series from the early 2000s based on a story by Stephen King. It followed Johnny Smith, a man who woke up from a coma with psychic abilities. He sees visions when he interacts with certain objects or senses. Afterward, he uses these visions to help solve crimes. By the end of the show’s six-season run, it was pulling a bit of a Supernatural, getting more and more “out there”.

Season six’s finale left fans with a serious cliffhanger; Johnny and his son could see Armageddon coming, and it was coming a lot sooner than they expected. Unfortunately, the show wasn’t picked up for a seventh season, so no one will ever know how and if they saved the world.

Revolution

After V, Syfy’s favorite heroine, Elizabeth Mitchell, starred in a new sci-fi series, Revolution. This story explored what would happen to the world if technology and electricity all malfunctioned and stopped working, leading to rationing, anarchy, and general apocalypse. Similar to V, though, the series only lasted two seasons. The season two finale left on a cliffhanger about the very energy they had been fighting and losing lives over. In the last minutes, the heroes thought they might have found a new source of power that could help save their people… and then the show was over, and nobody saw if they did find a source or what happened with it.

Lois & Clark: The New Adventures of Superman

While Lois & Clark isn’t some classic gem of Superman history, it still was a fairly popular superhero drama during its time. And, of course, it managed to have a bizarre, cliffhanger ending without any follow up.

In its final minutes, the married Lois and Clark find a baby on their doorstep and decide to raise it. Despite having been renewed for a fifth season previously, that season four finale was the last fans heard from the show. Now, who was the baby? Was it from someone local? Someone they knew? TV legends theorize it would have been another child of Krypton. No one truly knows, though.

Heroes

Ask any hardcore Heroes fan, and most of them will say stop watching after season 2. Between the loss of Bryan Fuller as a writer, the writer’s strike, and writing themselves into too many corners, Heroes was a promising show that didn’t follow through. Despite the amazing ratings of season 1 and the wonderful storytelling, the writers couldn’t keep the story going after they saved the cheerleader.

Heroes limped along until season 5 in which there was a carnival, and Claire had at least three deceased love interests. In the final episode, she jumped off a Ferris Wheel in front of a bunch of people to prove to the world that there were people with powers. While the season was sketchy, that concept was interesting. Not interesting enough to save the show, though, and it was canceled without knowing how the world would react to heroes.