THE BRAIN

Dr. Anthony Berol Blake runs Independent Thinking, a television show promoting a self-help, quasi-religious program resembling Scientology. But Blake isn't making his audience think any more independently – with the help of an alien organism he calls The Brain, he is using brainwashing and mind control. The only thing that stands between them and world domination is a brilliant but troubled high school student, named Jim Majelewski, with a penchant for pranks.

After being caught flushing sodium down a school toilet, Jim is punished and given a warning that he'll be suspended and won't graduate if he keeps doing pranks; reluctantly, Jim agrees to enlist in Blake's program as an alternative. He is then subjected to Blake's experiments, but he is immune due to being extremely smart and suffering from fantasy. He begins to have visions of The Brain as well as other hallucinations. Jim is aided by his girlfriend Janet and best friend Willie when Blake's assistant Verna attempts to take him back to the lab. Willie is killed by The Brain while Jim and Janet do their best to help free the residents of their town from Blake and The Brain's influence. The Brain and Verna brainwash the populace into believing that Jim is a murderer on a rampage; Janet and Jim's parents fall victim to the brainwashing and turn against Jim. Jim returns to Blake's headquarters as the latter plans to broadcast his Independent Thinking to a nationwide audience.

Jim beheads Blake in front of a live audience, revealing that he wasn't human. Jim and Janet are then chased by Verna. The Brain breaks loose and kills Verna before going after Jim and Janet. Cornered, Jim finds a canister of sodium and throws it into The Brain's mouth, blowing it up. Jim resumes a normal life with his parents as he and Janet drive off to school together.

Jim exposes Blake as non-human and destroys The Brain by feeding it sodium, freeing the town from mind control. He resumes a normal life with his girlfriend and parents.

The ending sees the protagonist using his prankster ingenuity—sodium, his original tool of rebellion—to defeat the monstrous Brain. By publicly unmasking Blake and turning the tables on the antagonists, Jim both liberates his community and validates his outsider status. The film closes with a wry nod to restored normalcy, but not before indulging in a final explosion of creature-feature chaos.