A train breaks down on a viaduct in the midst of a snow storm. Among the passengers are six teenagers who don’t know each other but start experiencing strange phenomena: hallucinations, visions of the dead, pestering voices. The ticket inspector is physically assaulted by one of them while another threatens passengers with a knife. The press writes them off as an organized gang of vandals. But to others, their actions are inexplicable and defy all logic. After the rescue, the police investigation turns up nothing. Their case is passed onto a psychologist who attempts to prove that the mysterious disappearances in the train are neither the fruit of their imaginations nor merely coincidence.