A man (Art Hindle) starts to have doubts about the treatment of his wife (Samantha Eggar) in an experimantal psychological centre run by a doctor (Oliver Reed) with unusual methods. The horror starts when people he knows (Susan Hogan) start being murdered by small strange creatures. This is not so much bloody horror as mind control. At the time when David Cronenberg was making this he was going through a difficult divorce and the pain he went through. The script is disturbing, though some of the performances as less than convincing, though Susan Hogan gives good support as the school teacher.