Tattooist Soo-na is one of the best tattoo-artists in South Korea. Her customers are the wealthy and the rich. She has no own studio, but therefore she visits her customers to make their tattoos. So they can keep their private life under wraps and Soo-na earns a lot of money. One day Ji-soo orders her to tattoo the head of the Medusa on his back. The Medusa is a monster from the Greek mythology with an ugly face and Hair made of snakes. Soo-na visits him regularly to draw always another snake to the head, which is quite strange. Why not getting the tattoo done in one session? But Soo-na has to face a terrible truth as she learns, that some girls in her city are missing. Because every time a girl get missing, Ji-soo orders another snake.