Two good friends live in together in a forrest. They are Geo, member of the warewolf clan and the human Niels. One night during a festival a human is killed. His neck shows bitemarks and the villagers cry that the monsters are to blame. And monsters always live in the woods. In order to prevent the humans from raizing the woods (our home) Geo and Niels decide to find the true culprit.

The year is Genroku, during the reign of Tokugawa Tsunayoshi. In a remote, snowbound village deep in the mountains, a body is discovered. The scene is gruesome—flesh from chest to abdomen has been savagely torn apart, as if by a relentless saw. Someone mutters: "The Saw Demon... It must be the Saw Demon’s doing..." As the cold rain continues to fall, sealing the village from the outside world, hidden motives and quiet fears begin to intertwine.