Uzumaki Series by Junji Ito, 伊藤潤二

Shortly after Shuichi Saito's father becomes obsessed with spirals -- snail shells, whirlpools, and man-made patterns -- he dies mysteriously, his body positioned in the shape of a twisted coil. Soon, the entire town is afflicted with a snail-like disease.

A sleepy town on the coast of Japan is under quiet, deadly siege, not by a person or group but by a primeval spiral shape whose victims include both parents of Shuichi Saito. In this second volume of the saga, Shuichi's girlfriend Kirie becomes further involved in the town's terrible secret when schoolmates start turning up as horrible human snails and something unspeakable is discovered within the walls of the local hospital.

Kurozu-cho, a fogbound town on the coast of Japan, is haunted by a recurring pattern: a spiral manifesting itself in increasingly terrifying ways. In this third and final volume, the town is cut off from the outside by devastating hurricanes. Kirie, her boyfriend Shuichi, and the other desperate survivors must face the impending horror. The movie version of Uzumaki will soon be released in the U.S.

Spirals... this town is contaminated with spirals...Kurouzu-cho, a small fogbound town on the coast of Japan, is cursed. According to Shuichi Saito, the withdrawn boyfriend of teenager Kirie Goshima, their town is haunted not by a person or being but by a pattern: uzumaki, the spiral — the hypnotic secret shape of the world. This bizarre masterpiece of horror manga is now available in a single volume. Fall into a whirlpool of terror!