Creeping parasites infect an isolated high-rise condominium in Montreal. The symptoms of the disease are frightening: victims commit acts of uncontrollable violence accompanied by unusual sexual behavior. A doctor races to discover the cause of the virus and tries to stop it from spreading.

David Cronenberg is one of Canada’s most prodigious artists for good reason—his films tap into the universal subject of the potential and indeed, likely, horrors of having a body. This early film is an unrelentingly pure genre B-movie, yet also a deceptively profound expression of fleshly anxieties.