Marebito is a 2004 horror film directed by Takashi Shimizu. The film follows a voyeuristic man named Masuoka (Shinya Tsukamoto) who becomes obsessed with videotaping fear after he sees a terrified man commit suicide by stabbing himself in the eye. Eventually, he discovers what appears to be an alternate dimension beneath Tokyo. He finds a naked woman chained to a cave there, and takes her back to his apartment. She cannot eat, drink, or speak, but one thing is for certain-- whatever she is, she wants blood.

The film is fascinating not only for its horror elements, but for its fantasy elements as well. The earliest scene of Masuoka crossing into a mountain range in an alternate dimension through the hidden underground tunnels beneath the Tokyo subway lines is something rarely seen in other horror films. The film has a mysterious ethos reminiscent of something from H.P. Lovecraft. Many attempts to explain the film include speculation that Masuoka is actually insane, that the characters and worlds he encounters actually just represent human ideas, or that F is actually his daughter. Marebito doesn't offer an explanation.