An intriguing mystery set in 18th-century Japan begins with the murder of Samurai Lord Inaba, right under the nose of the shogun. Judge Ooak and his assistant, 14-year-old Seiki, are entrusted with the case. They must track down the killer, and their only clue is a delicate origami butterfly, stained with blood. Seiki sets out on a perilous trip through the countryside, where he dodges extremely dangerous ninja, encounters angry, impoverished farmers, and is frustrated by an elusive assassin. This is the third electrifying book about Seiki, following THE GHOST IN THE TOKAIDO INN, and THE SWORD THAT CUT THE BURNING GRASS.