- Directors: David Cronenberg
- Producers: Claude Heroux
- Writers: David Cronenberg
- Genres: Horror, Sci-Fi
- Actors: Oliver Reed, Samantha Eggar, Art Hindle, Harry Beckman
An unconventional psychotherapist (Oliver Reed) has created a technique called “psychoplasmics.” He encourages his patients to “go all the way through it” and allow their negative emotions (rage, fear, etc.) to cause their bodies to undergo (usually radical) physical change. A man verbally abused by his father develops welts over his body as a way of expressing his pain. Another patient develops lymphatic cancer, supposedly a manifestation of his self-hatred.
In the case of the principal characters, it causes a woman, Nola Carveth (Samantha Eggar), to parthenogenetically birth strange, mutated children and, via a telepathic bond, have them act out whatever negative emotions the mother is feeling at the time, with disastrous consequences when her therapist brings those emotions to the surface. In the film’s climax, Nola is killed when a rescue attempt of her daughter fails, causing the titular Brood to attack Candice, and then die after their mother dies. Candice’s father, Frank (Art Hindle), takes her away, but it is hinted that, due to the extreme violence she witnessed and the loss of her mother, she has gained her mother’s ability, as shown by two odd welts growing on her. The film then cuts to credits, leaving Candice and her father’s fate unknown.