On a stormy summer day in the 1970s the wealthy Aosawas host a large birthday party in their villa on the Sea of Japan, which turns to tragedy when 17 people die from cyanide in their drinks. The only surviving links to what might have happened are a cryptic verse that could be the killer's, and the physician's bewitching blind daughter, Hisako, the only family member spared death. Inspector Teru is convinced that Hisako had a role in the crime, as are many in the town. The truth is revealed through a skilful juggling of testimony by different voices, including that of the mesmerising Hisako herself.