Kirie Goshima, a schoolgirl in the town of Kurouzu-cho, grows increasingly worried about her best friend Shuichi Saito's father, who has become fixated on collecting and staring at spiral patterns, neglecting everything else. After Shuichi's father commits suicide inside a washing machine, his cremated remains hover over the town in a massive cloud. This obsessive behavior begins to spread to Kirie's father and others, while throughout the town, people start to mutate into spiral-shaped creatures.
As the spiral obsession intensifies, it seems to infect the entire community, leading to bizarre and horrifying transformations. Kirie watches in horror as those around her become consumed by the spirals, both physically and mentally. The once peaceful town of Kurouzu-cho is now plagued by an eerie, unstoppable force that distorts reality itself.