The core twist of Poor Things lies in Bella's origin. It is revealed that Bella is actually the reanimated corpse of Victoria Blessington, an aristocratic woman who died by suicide to escape her abusive husband, Alfie. When Dr. Godwin Baxter found her body, she was brain-dead, but her unborn baby was still alive. Godwin transplanted the infant's brain into Victoria's skull, making Bella literally her own mother and daughter simultaneously.
In the film's climax, Bella's wedding to Max is interrupted by Duncan and Alfie. Curious about her past life, Bella leaves with Alfie, only to discover he is a tyrannical sadist who plans to forcibly circumcise her to curb her sexuality. In a shocking and darkly comedic reversal, Bella shoots Alfie, subdues him, and returns him to Godwin's lab. Inheriting her 'father's' surgical skills, Bella performs a brain transplant, placing a goat's brain into Alfie's head. The film ends with Bella triumphant—living happily with Max and her lover Toinette, ready to begin her career as a doctor, while a bleating Alfie chews grass in the garden.