Grafted

Wei's father tests a skin-regeneration serum on himself. The treatment causes his skin to grow uncontrollably and he dies by smothering. Wei inherits his obsession with the project and his incomplete notes.

Years after her father's death, Wei becomes a college student who continues his research using his notes. Her aunt moves her to New Zealand, away from China. Wei feels isolation while adjusting to a new country and school.

Wei's cousin Angie, along with Eve and Jasmin, treats her poorly and spreads cruel rumors. John, a severely disfigured but empathetic homeless man, provides some comfort. The social pressure foreshadows the desperation that follows.

Wei impresses chemistry professor Paul and is offered a lab post to salvage his grant. A flaw in Wei's father's notes prevents the new skin from binding properly, so Paul ultimately dismisses her from the post. Wei's ambition pushes her to find a workaround.

In desperation, Wei steals corpse flowers from a nursery to tackle the binding flaw. The flowers become the key ingredient to finally make the serum work. She takes a dangerous risk to advance the project.

With her aunt rarely home, Angie vandalizes a shrine Wei built for her father. The conflict escalates and Wei stabs Angie through the eye in self-defense and anger. She then rips away Angie's identity to keep her secret.

In a panicked move, Wei uses the perfected serum to bind Angie's skin to her own body. When finished, Wei effectively impersonates Angie and uses the new appearance to evade detection. The impersonation becomes central to her plan.

Wei learns that Paul has stolen her father's notes to claim the work for himself. She continues the project in secret, keeping up the Angie disguise while seeking a way to expose Paul. The power imbalance drives her deeper into deception.

Eve unintentionally exposes to the 'Angie' that she and Paul have a sexual relationship. Wei murders Eve with a power drill and uses the opportunity to further swap identities.

Wei replaces Angie's face with Eve's by using hair dye and colored contacts to steal Eve's identity. The disguise allows her to access more of the serum and keep Paul from noticing the fraud.

Posing as Eve, Wei locates the remaining serum sample Paul possesses. Paul remains unaware of her true identity and his own plans begin to crumble as the truth inches closer. Wei uses this to pressure him while keeping the notes out of reach.

Jasmin visits Wei and uncovers the frozen heads of Angie and Eve in a hidden fridge. Wei smothers Jasmin to protect her secret. The discovery intensifies Wei's spiral toward total control.

Paul confronts Wei in a confrontation about the scandal, openly admitting he plans to sell the notes. Wei paralyzes him with an injection and doses him with the flawed batch that killed her father.

A noisy neighbor calls the police after discovering Paul's death. Wei tries to flee, but the sample in her pocket shatters as she rushes to disappear. Her escape ends in a tense standoff with authorities.

Months later, Wei's aunt encounters a lookalike Wei. An old homeless woman wrapped in John's blanket is revealed to be Wei, now merged with John's decaying corpse. The transformation marks the final erasure of Wei's individuality.