Warning: Wikipedia contains spoilers
Dark City is a 1998 movie directed by Alex Proyas. The movie is about John Murdoch (played by Rufus Sewell), a man who has lost all of his memory, including who he is. After waking up in a bathtub at a hotel, he recieves a phone call from Dr. Daniel Schreber (played by Kiefer Sutherland) to leave the hotel immediately. According to Schreber, a group of men (who may not actually be humans), refered to in the movie as The Strangers, are coming to the hotel to find Murdoch, and it would be best that he tries to escape them. Murdoch escapes them, and shortly afterwards finds out his name and that he has a wife named Emma (played by Jennifer Connelly). Unfortunately, he also finds out that he is wanted for a string of serial killings, which he has no memory of and doesn't have the urge to commit. Nonetheless, he is being tracked down by police inspector Frank Bumstead (played by William Hurt).
He also starts to find strange things happening around the city, all of which seem to have some connection to The Strangers. For instance, he's noticed that there are times when everyone in the city falls asleep at the same time. He's also noticed that it is always night in the city. And strangest of all, he's noticed that he has some sort of psychokinetic power, which The Strangers seem to also have.
Having learned all this, Murdoch sets out to clear his name of the serial killings and find out why he's lost his memory, and why so many strange things are happening in the city. However, he has to deal with The Strangers apposing his attempts to learn the truth about the city, especially Mr. Hand (played by Richard O'Brien), a Stranger who seeks to become human.