Thirst is a 2009 South Korean horror film written, produced and directed by Park Chan-wook. It is loosely based on the novel Thérèse Raquin by Émile Zola. The film tells the story of a Catholic priest—who is in love with his friend’s wife—turning into a vampire through a failed medical experiment. Park has stated, "This film was originally called 'The Bat' to convey a sense of horror. After all, it is about vampires. But it is also more than that. It is about passion and a love triangle. I feel that it is unique because it is not just a thriller, and not merely a horror film, but an illicit love story as well."