A young couple, Angus and Caroline Jenson, hold a seance to contact their recently-deceased son. Something goes wrong and Angus is thrown against the wall by a powerful spirit. When he starts to experience blackouts and has a vision of a car plunging into the water, he visits the Department of Parapsychology at Clyde for counsel. As he becomes increasingly violent, the team races to determine who or what has possessed him.
