"You're a..." "Say it" "Priest"

In 1922 German director F.W. Murnau brought the first vampire to screens in his partial adaptation of Dracula in the film Nosferatu. However, it is another Murnau film that informs Korean director Chan Wook-Park's newest film Thirst, this being Murnau's Sunrise. That older film, which looks at a relationship made fragile by the grim specter of lies and death is given a jolt of the extreme shock and awe that has made Park an international sensation in films like Oldboy and Sympathy for Lady Vengeance.

The film, which would throw the fans of Twilight in a tizzy has built a complex artifice around a very primal morality play. In the film a well intentioned priest undergoes a radical treatment to aide in the curing of a rare blood disease. At first it appears that the disease is killing him but instead it has turned him into something beyond human. People having gotten word of his miraculous recovery and think he is truly blessed. The priest, Sang-Hyun (played by Sang Kong-hu) slowly becomes aware of what he truly is and in the course of his visits the sick he meets Tae-Ju (as played by Kim Ok-Bin). The woman is in an abusive relationship with her husband, or at least alleges to be in one. She's certainly very upset, something Park gets across in a scene that while the husband sleeps Tae-jun continues to jab cutting sheers towards the inside of his mouth and then removing them at the very last moment. A more conventional director would do this once and it would big moment. Park teases this out as she stabs down for almost a minute of screen-time. Park has always had an eye for faultless composition and artistic framing. He also knows how to produce a cut that is devastating to an audience. All these hallmarks are on display here. Though, I've no doubt Park could make a senses-shattering scary film, conventional scares is not quite whats going on here.

Instead of conventional scares Wook-Park is going for genuine human horror at what human-beings are capable of when morality is cast aside by the promise of power and lust. When Sang-Hyun's whose bloodlust is growing is asked for help by Tae-Ju he starts the two down a path that under Wook-Park's direction unspools into memorable moments of darkness. The film moves slowly, but this pacing lends power to Wook-Park's sudden swerves where characters behave in surprising ways and the plot rockets forward as our protagonists dig themselves into a deeper and deeper hole.
I'd like to go into more detail about the Sunrise comparison and the nature of these character's denigration but I feel it spoils a lot of the film's twists. I would be happy to go into more detail if its requested in the comments. Let me know.