It’s not uncommon for sci-fi movies to have several endings before the director and the studio decide on the one that will hit the theatres — and the fans can only hope to catch a glimpse of the alternative cuts on DVDs or Blu-rays. As it happens, these highly successful sci-fi films almost ended differently.

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Francis Lawrence’s post-apocalyptic sci-fi thriller, loosely based on Richard Matheson’s novel of the same name, shows the world where humans were infected by a virus that either killed or transformed them into bloodthirsty mutants called Darkseekers. The story follows Robert Neville (Will Smith), New York City’s sole human survivor, who is immune to the virus and works on developing the cure while fending off the mutants. The theatrical cut has a rather grim but heroic ending — the Darkseekers invade Neville’s lab just as he finds a cure to the virus. To protect it, save other survivors, Anna and Ethan, and give humanity a fighting chance, Neville blows himself up along with the Darkseekers.

The alternative ending, released on the DVD special, was much closer to the original novel and portrayed Neville in a darker light. In it, Darkseekers still storm the lab, but instead of sacrificing himself, the virologist realizes the monsters’ real motivation — to free the female test subject, who turns out to be the mutant leader’s mate. After Neville sets her free, the Darkseekers depart peacefully, leaving him to contemplate the atrocities he committed during his experiments and the monster he became in the eyes of the infected. While this version had a seemingly ‘happier’ ending, with all the survivors making it to the camp, the test audiences preferred the heroic act and the dramatic explosions.

This popular sci-fi psychological thriller stars Ashton Kutcher as a college student, Evan Treborn, who finds out he can travel in time and attempts to change the traumatic events that affected himself and his friends in the past. His actions have domino-style consequences, messing up the present in unpredictable ways. In the familiar, melancholic ending, Treborn decides to take the moral route and time travels one last time to ensure he never gets together with the love of his life, saving her and his friends from the impending pain.

While the official ending was bittersweet, it didn’t come close to the darkness of the director’s cut that almost made it to the screens. In it, Treborn travels back to when his mother was pregnant and strangles himself with his umbilical cord, ensuring that his time-traveling ability/curse isn’t passed down to the next generation and his friends go on to live happy lives, unimpacted by his meddling. A dark ending, even by sci-fi measures.

Christopher Nolan’s hugely successful sci-fi epic is set in a world where humanity was near-extinguished by an environmental catastrophe and had to find a new home. The story centers around the former NASA Pilot, Cooper (Matthew McConaughey), who joins a top-secret government project and must leave his daughter behind and travel through a wormhole in the hopes of finding refuge for the endangered humankind.

After a rollercoaster of time and space travel twists, Cooper stumbles upon a Tesseract that allows him to leave hints on saving humanity for his daughter at different times in her life. The movie has a relatively happy ending, with the protagonist making it out alive thanks to the love for his daughter and re-uniting with her elderly version and his partner. However, the rumored original ending was much darker and open-ended. In it, Cooper is killed when the wormhole collapses on him, making it unclear whether or not he managed to survive, send a message to his daughter, or even save humanity. Fortunately, this ending never made the cut.

Ridley Scott’s sci-fi horror gained cult status through the years, launched one of the most successful franchises, and established Ripley (Sigourney Weaver) as one of the most badass female sci-fi characters. The story follows a crew that finds itself trapped aboard a spaceship called Nostromo, with a deadly alien methodically eliminating them one by one. The theatrical ‘happy’ ending shows the sole survivor, Ripley, escaping Nostromo, blasting the alien into space, and entering herself and the cat Jonesey into stasis to reach Earth.

The original ending that almost happened had a very different tone. It saw the Xenomorph winning the final confrontation, ripping Ripley’s head straight off, and using trickery to record the captain’s final log and potentially lure another unsuspected human crew onboard. Fortunately, the studio didn’t want to miss out on a sequel opportunity and put its foot down, threatening to fire Scott if he refused to change the ending — much to the joy of the fans of the franchise and Ellen Ripley.

There’s hardly a person out there who hasn’t seen or at least heard of James Cameron’s cult machine-killer sci-fi action film. It spawned a successful franchise, established Arnold Schwarzenegger as an ultimate action star, propelled Cameron’s director career, and introduced one of the most iconic catchphrases. The story follows a cyborg assassin (Schwarzenegger) sent back in time to eliminate Sarah Connor’s (Linda Hamilton) unborn son, who is bound to lead a human resistance against a rogue AI, Skynet, in the future.

The action-packed film ends with a famous factory confrontation, where Reese (Michael Biehn), Connor’s human protector sent from the future, sacrifices himself to save her from T-800. The pregnant Connor then closes the time loop neatly, taking the fateful photograph. While it might look as if Cameron has decided to launch a sequel only due to the original film’s success, as it turns out, he had it in mind all along. The original ending shows a man picking up a computer chip from the crushed T-800 and sending it down to the R&D department. The camera zooms out to reveal that the building belongs to Cyberdyne Systems — the company that will invent the apocalyptic Skynet. However, Cameron decided to remove the scene, not to take away the focus from Connor’s emotional journey, rightly believing that the audience will fill in the gaps.

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