Doctor Caligari, a traveling mesmerist who journeys from town to town with a sleepwalker under his control, leaving a trail of grisly murders in their wake. When a young woman’s boyfriend disappears mysteriously, she believes that the enigmatic Caligari is somehow responsible. The problem is — nobody believes her.

When hundreds of videotapes showing torture, murder and dismemberment are found in an abandoned house, they reveal a serial killer's decade-long reign of terror and become the most disturbing collection of evidence homicide detectives have ever seen.