Vortex (2000)

In a small town in Japan, Kirie comes upon her boyfriend's father silently videotaping a snail. He seems unaware of her presence and she thinks no more of it. Later, the mans obsession with spirals becomes more and more bizarre, ending in his suicide in a washing machine which turn his body into a spiral. Soon other inhabitants become possesed with different forms of spirals, one student seems to be mutating into a snail, another's hair becomes strangely medusa-like. The entire town becomes possesed.