Series finales can either make or break a show. The science fiction genre, in particular, often weaves a tale of intrigue leading up to its finale episode. Because of this, an unsatisfying ending can make audiences feel as though the entire series has been ruined.

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Throughout television history, some sci-fi series have been revered for their fantastic endings. Series such as Babylon 5, 12 Monkeys, Fringe, and Star Trek: The Next Generation all nailed their finales, creating the perfect end to the beloved shows. However, others have not been so lucky, and upset fans have been quick to share their disappointment.

10 Quantum Leap Audiences Wanted A Happier Ending

Sam returns to save his friend in the Quantum Leap series finale

When the popular series Quantum Leap ended its run in 1993, audiences were accustomed to a more traditional happy ending. So, when the series ended with the main character, Sam, sacrificing his happy ending and leaping back to help a friend, only to never return, it wasn't well-received.

A more modern audience might have been more accepting of the show's sad end, but in 1993, it was too dark. It left audiences feeling as if they had followed the series for five seasons, only to be let down.

9 Haven's Finale Rendered The Plot Useless

Audrey and Nathan looks upset in the Haven Finale

Haven was a supernatural crime procedural series about the weird happenings in the fictional town of Haven, Maine - a safe haven for people with supernatural abilities. Loosely based on the novel The Colorado Kid by Stephen King, the series followed FBI agent turned Haven police officer Audrey and her partner Nathan as they solved crimes revolving around the super-powered residents.

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Things go off the rails in the series 5th and final season as it explains the lore of the town and Audrey's part in it. However, viewers found the explanation lacking and the conclusion left them feeling like there was no point in the series at all.

8 The Ending Of V Drained Audiences of Hope

Anna from V

A remake of the 1983 miniseries of the same name, V aired for two seasons beginning in 2009. The plot revolved around a group of technologically advanced extraterrestrials that arrive on Earth, claiming to have come in peace. However, it's soon shown to viewers that their ulterior motives are nefarious.

The first season was graciously received by critics and audiences alike, with special praise for the show's intriguing storylines and smart performances. However, Season 2 opened up more questions than were answered, and the end of the series saw little resolution. In fact, the final episode saw the death of multiple main characters and a message that the V population was unstoppable. While another season might have corrected this, the series cancellation left viewers feeling as though there was no reason to have watched the series, if no true resolution was ever possible.

7 The Penny Dreadful Finale Was A Surprise To Viewers

Vanessa Ives in the Penny Dreadful Finale

For three seasons, Penny Dreadful aired to fantastic critical reviews and an avid cult following. A period piece set in 19-century Victorian England, the series uses many characters from classic gothic fiction within the storyline, including Victor Frankenstein, Dorian Gray, and Dr. Jekyll.

The series finale came as a jolting surprise to viewers, as it wasn't announced before the episode aired, alerting audiences to its end with a simple title card after what was presumed to be a season finale reading, "The End." Not only were fans upset by the abrupt ending, but the story also left multiple loose threads unresolved.

6 Merlin's Finale Was A Disappointment

An aged Merlin waits for Arthur's return in the Merlin Finale

Merlin, loosely based on the Arthurian legend, aired for five seasons, boasting a large audience in both the UK and the US. After a series filled with beautiful character development, fun writing, and interesting storylines, the finale all but ruined the entire show.

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While beautifully executed, the finale left viewers with too many unanswered questions, and the tragic end for the characters angered many fans. The ending left fans feeling disappointed in the time they invested in the series and unsatisfied with how the story ended.

5 The Whispers Ended With A Shocking Revelation

Claire runs to save her son in The Whispers Finale

When The Whispers pilot aired, audiences were unsure what route the story would take. A group of children was committing questionable and dangerous acts while playing a game with an unseen entity named Drill. FBI child specialist, Claire Bennigan, played by the incredibly underrated Lily Rabe, begins to put the horrific pieces together. Quite quickly, audiences discover Drill is part of an alien species and the series spirals into science fiction chaos.

With children seemingly the enemy's main target, audiences assumed there would be a positive resolution by the season's end. However, the series instead concluded with many children being taken from the planet by the aliens. This came with the surprise twist that the extraterrestrials didn't arrive to take over the planet and instead came to take Earth's children. Without a second season, viewers were left without ever knowing the true motives behind the abductions.

4 ALF Had A Dark Ending For A Funny Family Series

ALF is about to get captured in the ALF series finale

ALF, an acronym for "Alien Life Form," was a 1980s sitcom about an alien that crash lands in the home of a middle-class suburban family, The Tanners. The family takes ALF in and keeps him hidden from the government as he becomes part of the family.

The series was a family-friendly hit and the lovable ALF, performed by a puppeteer, quickly became a pop culture phenomenon. So, it came as a big shock to viewers when the sitcom ended on a dark and ominous note. Attempting to reconnect with his family, ALF is interrupted when he is caught by the US military. The cliffhanger was never resolved, as the series never aired another episode, and fans were left without knowing the fate of the lovable alien.

3 Heroes Never Reached Its Potential

Claire runs in the Heroes Finale.

The superhero drama Heroes started off with immense potential. The series tells the story of ordinary people that discover they have superpowers. Together, they must work to save the world. With creative characters, a fantastic ensemble cast, and promising storylines, the series quickly garnered a large fan following. However, by Season 4, viewership had steadily declined due to the show's slow pace and increasingly sporadic storytelling.

Expecting a fifth season, which never materialized, the series ended with the Season 4 finale leaving viewers disappointed that Heroes never seemed to reach its fullest potential.

2 The X-Files Finale Went Off The Rails

Mulder and Scully in The X Files Finale

The X-Files is one of the most popular shows in sci-fi history. The series, which follows FBI agents Fox Mulder and Dana Scully as they investigate unsolved paranormal cases, became a pop culture phenomenon, spawning multiple movies, spin-offs, and merchandise, as well as a revival series in 2016.

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After eleven seasons, The X-Files finale was an incoherent disaster that left fans confused and upset. Jam-packed with too many plots, the finale tried to wrap up too many things too quickly, which inevitably led to an unsatisfying end.

1 Lost Ended With A Tired Cliche

Jack and Locke shake hands as they join the others in the church in the Lost finale

Lost reinvented the genre when it aired in 2004. The series followed a group of plane crash survivors as they navigated life on an island full of surprises. Week after week, the series threw twists out at its characters and the audience, leaving viewers with plenty to discuss at the office water cooler. Fans spent five seasons trying to decipher what was happening on the island, which led to a multitude of theories.

When the season finale aired, audiences tuned in with excited anticipation to learn the truth about the secrets of the island. Unfortunately, the explanation was a tired cliche that many people had thought of during Season 1. This end left people feeling led on by years of the writing team amping up a surprise ending and wishing they hadn't wasted five years' worth of energy trying to figure it out.

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