Dr. Bill Cortner, portrayed by Herb Evans, is an exceptionally skilled surgeon who manages to save the life of a patient during a surgery led by his father, Dr. Cortner, played by Bruce Brighton. Utilizing controversial techniques from his research on amputated limbs, Bill's methods raise ethical concerns, especially since they involve using body parts from deceased patients. While Dr. Cortner acknowledges his son's talent, he cautions him to be cautious in his work.
As Bill plans a weekend with his fiancée, Jan Compton, an urgent call from Kurt, his assistant, interrupts him, alerting him to a crisis in the basement of their country house. In a tragic turn, Bill is involved in a car accident that decapitates Jan. Desperate to save her, he brings her head back to the country house, determined to transplant it onto a new body. He harbors one of his previous experiments locked away in the basement, which becomes increasingly aggressive. Meanwhile, Jan's surviving head resents its unnatural state and conspires with the creature in the closet, plotting a dangerous escape.
As Bill searches for an ideal female body, he reconnects with an old acquaintance, Donna Williams, offering her a chance at beauty restoration through his father's surgical skills. However, Bill's unorthodox methods lead to unforeseen consequences when he brings Donna back to the country house, causing a chain reaction that culminates in horror.
The film opens with a dark screen, alongside a woman's anguished voice begging, "Let me die. Let me die." This chilling start sets the tone as a man lies on an operating table surrounded by worried doctors. When the patient dies, Dr. Cortner laments, "I should have known he was a good as dead when they wheeled him in." Nurse Jan attempts to console him, asserting the efforts were valiant. Seizing the moment, Bill requests to take over the procedure to prove his pioneering techniques can avert death, eventually succeeding in reviving the patient.
Post-surgery, father and son debate the ethics surrounding their work, particularly regarding missing limbs from their hospital. When Jan arrives, Bill reassures her of their wedding plans. Yet, a message from Kurt about a calamity at the country house propels them into a disastrous car crash, which leads to Jan's tragic fate.
Bill's obsessive quest to find a body for Jan's head takes him through dark alleys and strip clubs, as he seeks a potential candidate amongst unknowing women. As Jan navigates her new reality, she forms an alliance with the creature stowed away in the closet, setting the stage for revenge against Bill.
The film escalates into graphic chaos as Bill’s nefarious plans unravel, ultimately leading to confrontations with both the living and the grotesque. Jan's silent determination signals a haunting end as the sinister experiment spirals out of control, leaving viewers captivated by the intertwining tales of love, loss, and the macabre consequences of unchecked ambition in the world of science. “I told you I’d bring you a body. A beautiful one. Soon it will be yours,” Bill declares to Jan, unaware of the chaos his obsession will usher in.
In the climax, the house becomes an arena for revenge and survival as the line between life and death blurs terribly, culminating in tragic yet darkly absurd demolitions of responsibility and ethics in the pursuit of love. The story fades to black with Jan's chilling laughter echoing, forever haunted by what transpired.
