An employee at a Japanese embassy in a South American country is kidnapped but Furuhata, who is there on holiday, begins suspecting that the man was killed by none other than the Ambassador Extraordinary and Plenipotentiary himself.
Three successive presidents of the Horibe family company die in mysterious circumstances following the lyrics of a creepy nursery rhyme and all according to the plan made by an 11-year-old boy.
Ichirô Suzuki, a baseball player obsessed with fair play, murders a man who was blackmailing his brother who is none other than Furuhata's faithful friend Mukojima.
Kyoko Kagami is a pen name for a pair of twin writers. After one sister kills the other, their technical advisor Furuhata investigates. His investigation is complicated by his feelings for the surviving sister.