A very unhappy Nola (Samantha Eggar) checks herself into the Somafree Institute of Psychoplasmics for "intensive therapy." Sharing custody of young Candice, Frank (Art Hindle) agrees to allow his daughter to stay at the institute while Nola is being treated by Dr. Raglan (Oliver Reed). The doctor's methods include pushing patients to fight through their emotions -- typically anger (his book is entitled The Shape of Rage). Raglan's experimental therapy is so extreme and intense that it will sometimes bring about changes in his patients, not just emotionally but physically as well. As far as Frank is concerned, Nola can submit herself to as much therapy as she wishes, but when Candice comes home covered in bruises, he is determined to keep his daughter away from Nola and anything to do with psychoplasmics.
The father soon begins searching for hard evidence so that he can openly accuse Dr. Raglan of fraud. He finds a former patient of the institute and sees firsthand what exactly can result from the doctor's therapeutic means. While Candice is staying with Frank's mother-in-law, the young girl's grandmother is murdered, and Candice catches a glimpse of the killer, leaving her in shock. More murders occur, Candice is kidnapped, and Frank learns that Dr. Raglan has made his other patients leave the institute so that he can focus solely on Nola.
As my uncle once told me, many of Cronenberg's films deal with some sort of metamorphosis. Marilyn Chambers develops an odd lesion near her armpit following an unconventional operation in Rabid (1977), James Woods becomes a human VCR in Videodrome (1983), and, of course, Jeff Goldblum becomes... well, you know, in the director's 1986 remake of The Fly. Even in his later films, which don't involve bodily mutations, there is almost a psychological metamorphosis. In A History of Violence (2005), for example, Viggo Mortensen's character begins as a small-town diner owner and seems to turn into a cold, deadly gangster (it's perhaps closer to a regression but in the viewers' eyes -- and the eyes of his family -- it can be considered a metamorphosis). There are metamorphoses throughout The Brood: the physical changes in Dr. Raglan's patients, Frank and Nola's relationship, Ralgan and Nola's sessions, little Candice witnessing things beyond her years, etc. It's the essence of the film. As the director suggested, we begin with Kramer vs. Kramer, but we end with purebred Cronenberg.
The controversial ending was edited by a mere few seconds in the U.K. But those small cuts, intended to make the scene less intense, made Nola's actions appear much more sinister. The Brood and many of Cronenberg's films seem to be an acquired taste. But they are unquestionably the products of an intelligent, thoughtful filmmaker who can tell a great story. And if nothing else, viewers can learn this from The Brood: If ever you hear a noise in the kitchen, don't investigate. You probably don't want to know what's rooting around in the cupboards.