10 Awesome Sci-Fi Twists You Never Saw Coming
5. Moon - Sam Is A Clone
If you haven't seen it, you definitely should check out Duncan Jones' Moon from 2009. It's how science fiction should be made, and it stands as one of the most realistic and plausible stories in the genre, but you wouldn't know just how plausible it could be unless you learned the twist.
The surprise in Moon didn't come at the end. Rather, it hit the viewer fairly quickly in the transition from the first to the second act. Up to that point in the film, Sam Rockwell is the only astronaut working on the Moon to harvest Helium-3 as an alternate energy source to oil, and the Moon has a ton of the stuff.
He's there to watch over the equipment, make minor repairs, and ensure it all runs smoothly, but it's a lonely existence. He video chats with his wife on Earth, and only remains for three years, but when something goes wrong, his world completely changes.
Not only is Sam not the only person on the Moon, but he's also a clone, and every three years (or, if something goes wrong), an old clone dies, and a new one takes his place. This ensures the minimal cost of operations for the corporation mining the Moon but challenges the very humanity of the film's central character. It was a shocking twist, that turned a plausible Sci-Fi film into one challenging our morality, and what it means to be human.