Layering its images one on top of the other in a manner resembling the spiral shell of the title, this novel is written in a style that deliberately obscures whether the story is dream or reality, and whether it takes place in the distant mythological past, the future, or the present world. The story begins two months after a man named Innami washed up on the shore and was discovered by the owner of a modest bed-and-breakfast nearby, who also runs a gift shop on the beach. Since then Innami has been staying at the B&B and helping out by watching the store during the day. Since the place sees few customers, he spends much of his time writing a story of sorts to explore the question of why he is able to go on living. Then one day he comes across an old booklet on one of the shelves titled Raho yonsen-nen ki (yaku) (Spiral Shell Four-Thousand-Year Record [Translation]). He begins copying out the story, and from this point on the events in Innami's own story and events in the story within the story become melded into one.
Innami is transformed into a white lizard and gobbles up a cricket, head first. Innami vanishes and the story turns to that of a goddess who lives near the gift shop, on her way to a music store to pick up a lute she had left for repairs . . . Much of the work's appeal comes from the highly sensory prose in which it is written, filled with onomatopoeia and mimetic words, dialect, and a blend of classical and contemporary language.