Evan Russell, a young American man, loses his mother to cancer. After her funeral, he gets into a physical altercation at the restaurant where he works and loses his job. On his friend's advice, Evan travels to Italy and meets a flirtatious girl named Louise. Interested in pursuing a relationship with her, he starts living in a small town in southern Italy, working at a local farm. Louise, who initially rejected Evan, finally has sex with him without using a condom. The next morning, she wakes up before he does and has a monstrous appearance. After leaving, she kills a cat. After a few dates where they explore the town together, Louise asks Evan about his family. Although he is reluctant to reveal details, he relents and asks Louise to tell him something about her. Louise takes out a contact lens from her right eye to show Evan that she has
heterochromia. Evan sees the same condition reflected in the women on many of the paintings in the museum and also on the cover of a book. One night, Louise is having dinner with Evan when her skin condition becomes worse. She runs off the street and is followed by a tourist who mistakes her for a prostitute. Louise unwillingly kills him after she mutates into a reptilian creature. Evan, who has been working illegally on the farm, has to leave when immigration police arrive. With nowhere else to go, he visits Louise's house. The door is chain-locked, through which he sees blood on the floor and hears a strange voice. He breaks the chain to open the door and finds an octopus-like creature on the floor wearing Louise's dress, trying to reach a syringe. He quickly picks up the syringe and injects it into the creature's neck. Louise reveals to Evan that she is a 2,000-year-old mutant. She is the woman in all of the paintings of women with heterochromia. Every 20th spring, she finds a man to impregnate her, and her body uses cells in the embryo to recreate her while she changes into different creatures. Shocked, Evan leaves. Louise follows him and tells him more about the condition. She reveals that she avoided using a condom during intercourse to purposely get pregnant. She also reveals that if she falls in love, the hormones will stop the process and turn her mortal. Evan asks if she is in love with him; she replies she is not and would not give up her immortality for anyone. Evan asks her to spend her last 24 hours with him before she re-evolves. They spend all night talking to each other. In the early morning, Louise takes Evan to the ruins of
Pompeii, where she was born, and tells him her family history. The time comes, and Evan makes one last attempt begging her not to change. Louise says she has no control over it and warns that she may attack him. He refuses to go, so Louise lies down with her head on his lap and listens to Evan talk about the experience of being mortal and all its positive aspects. As the sun rises, Evan calmly looks down at Louise as he hears a grotesque sound. However, he finds Louise still in her current human form while
Mount Vesuvius, the volcano that resulted in the death of Louise's family, erupts in the background. ==Cast==