A young woman named Soo-hyeon is struggling against cancer and her older sister Ji-hyeon decides that she should take her home so that she can enjoy what little time she has left rather than spend it in a hospital. Ji-hyeon is a mute, because of a car accident that impaled her throat. She buys a long-haired wig for her sister so that she can go out without feeling ashamed; what she doesn't know is that the wig is cursed. Soo-hyeon is happy with the wig on; she begins to look and act healthier and more attractive, and leaves the house often. Soon, however, she begins to try and steal Ji-hyeon's boyfriend. He breaks up with Ji-hyeon but is not interested in Soo-hyeon. One day, one of Ji-hyeon's friends finds out that her husband is cheating on her. Soo-hyeon lends her wig, saying that she will feel prettier and better. The next day however, the friend is found dead with her husband, covered in hair. Soo-hyeon's wig returns to her, mysteriously. She cruelly ignores Ji-hyeon and is plagued with frightening images of the friend's demise. The next day, she tries to have sex with Ji-hyeon's ex, but Ji-hyeon picks her up and the two drive home. Soo-hyeon goads her, angering Ji-hyeon. At home, the two don't speak until Soo-hyeon washes the wig and Ji-hyeon sees a ghost in it. She grabs the wig and locks Soo-hyeon in her room, then cuts the wig to shreds. The cancer returns and Soo-hyeon has to go back to the hospital, unhappy and refusing to see her sister. She escapes the hospital after not taking her medication. We see a disturbing scene of Soo-hyeon pulling pills from her bloody scalp. It is revealed that the wig belonged to a man who was in a romantic relationship with Ji-hyeon's ex. Being gay, he was shunned by Ji-hyeon's ex and beaten by a group of teens, cutting his long hair. He then committed suicide. The ghost of the man now possesses Soo-hyeon and is trying to get back with Ji-hyeon's ex. As they kiss, Soo-hyeon's hair grows at an impossibly fast rate. Ji-hyeon appears and sets fire to the long hair, freeing her sister and destroying the ghost. Unfortunately, she hallucinates that the ghost is in the place of her sister and beats her to death. As Soo-hyeon dies, her sister cries at what she has done. The film ends with a photograph of the two girls as children, before Soo-hyeon's cancer and Ji-hyeon's speech loss.
Critical reception for The Wig has been mixed. DVD Talk and Shock Till You Drop were both relatively ambivalent in their reviews, as both felt that the movie wasn't the best that Asian horror had to offer but still had some viewing value to it that people would enjoy. Bloody Disgusting echoed these sentiments, as they felt that the movie "requires a lot of commitment on the part of the viewer" but that the payoff was "worth it, because as strange as it is, you might not have seen anything quite like it before."
Trivia
Chae Min-seo actually shaved her head for the movie.
