Aliens, astronauts, time travel—you name it, there’s a dazzling sci-fi film about it. That makes compiling a list of the best sci-fi nearly impossible. It’s hard to know where to start, and where to stop. To understand where sci-fi films came from, you need to head back to the dawn of the cinema age. Right at the beginning, Metropolis, released in 1927, used groundbreaking visuals to create a...