Exte (エクステ Ekusute) is a 2007 Japanese horror film written and directed by Sion Sono, and stars Chiaki Kuriyama, Ren Osugi, and Megumi Satō. The title is a Japanese slang shortening Romanization of the English term "extension" from "hair extension".
The plot involves an aspiring hair dresser (Kuriyama) who becomes the infatuation of a tricophilic man who sells hair extensions to nearby hair salons. The source of the hair is the stolen corpse of a girl whose dead body continues to grow beautiful and voluminous black hair that comes alive, driving those who use the extensions insane or killing them. The movie was released in the U.S. as Exte: Hair Extensions.
In a shipping container, customs agents discover a huge amount of human hair used as materials for hair extensions, along with the dead body of a young girl with a shaved head. The corpse is transported to the morgue, where the results of the autopsy determine that the girl's internal organs have been harvested, the victim of a black market human organ racketeering ring. The morgue night watchman, a closet tricophile named Yamazaki (Ren Osugi), is infatuated by her beautiful hair and steals the body away to his home. He finds that the girl's body has begun to grow hair—from her head, vacant eye sockets, tongue, and various open wounds. He is delighted and encourages it to grow, harvesting it to make hair extensions to sell. Notwithstanding the hair controls and kills its wearers, causing them to experience the dying memories of the corpse girl, including the last thing she sees on the bloody operating table: the smiling mouth of the man who killed her.
Meanwhile, Yuko (Chiaki Kuriyama) is a young apprentice hair stylist at a local hair salon (named after alleged child murderer Giles de Rais. One day, her irresponsible older sister, Kiyomi (Tsugumi), dumps her eight-year-old daughter, Mami (Miku Sato), on Yuko and Yuko's roommate, Yuki (Megumi Satō). Mami shows signs of abuse. Yuko allows Mami to stay with her, telling her to stay home while she goes to work each day, concerned about the abuse she has suffered from Kiyomi.
Out on the street, Yamazaki spots Mami trying to find Yuko's hair salon and finds her hair exceedingly beautiful. He introduces himself and helps her find Yuko's work place. When he sees Yuko, he's additionally enchanted by her hair, but quickly runs off. He returns the next day, explaining that he sells hair extensions. The workers at the salon are impressed by the hair's quality and try them out. That night, Kondo, one of Yuko's co-workers who tried on the extensions, is killed when the hair begins sprouting from her eyes, head, and mouth.
Yuko later discovers that Kiyomi has been tricking Mami into letting her enter Yuko's flat so that she can raid her food and clothing. Yuko and Yuki refuses to return Mami to her due to the abuse, and Kiyomi returns one last time while they're away, stealing more clothing, one of Yamazaki's hair extensions, and dragging Mami back to her boyfriend's home. After punishing Mami by locking her in the closet, the extension comes to life and slaughters Kiyomi and her boyfriend. Mami escapes the hair by jumping out of the window into a bush, injuring herself. At the hospital, detectives have Yuko identify Kiyomi's body.
Participating in a hair dressing workshop, Yuko uses Mami as her model and attaches one of Yamazaki's hair extensions to her hair. The workshop is interrupted by the detectives, who're there to inquire about Kondo's death, and Yuki takes Mami home. After the detectives leave, Yuko realises that the hair extensions are the linking factor in the various deaths and races home to Mami. While Mami is playing, hair begins to seep into the apartment. Yuki rushes Mami to safety, but is strangled to death by the hair and Mami faints. Yuko enters the hair-filled flat and tries to free Mami, but is choked unconscious by the hair. Yamazaki arrives in time and commands the hair to spare Mami and Yuko and takes them back to his living hair-covered home. There he discovers the detectives caught in the hair, who searched his house when they discovered that he was the one responsible for the deaths. He kills them as Yuko wakes up.
Yamazaki explains that after her organs were harvested, the girl's hair continued grow, carrying on her grudge against society. He wishes for Mami and Yuko, two living amongst and making a career around hair, to stay with him and the corpse forever. Yuko rejects him, and to protect Mami, begins taunting Yamazaki, enraging him and causing him to reveal that he willfully allowed the hair to possess him, his tongue hairy and his blood and limbs replaced by hair. In anger, he cuts a few of Mami's hair, which begins to bleed. While in wonder of what he has just seen, the blood and Yamazaki's smiling cause the corpse to associate him with the man who killed her and she suddenly sits up, immobilising him and slicing him to pieces with strands of hair, killing him while Yuko and Mami escape. Her grudge satisfied, the hair disappears and the girl's body returns to normal, finally at peace. Having escaped, Yuko and Mami sit on the beach and Yuko asks Mami to live together with her permanently, which Mami happily accepts.