宝石商リチャード氏の謎鑑定

College student Seigi Nakata steps in when drunks harass a strikingly handsome foreigner near Yoyogi Park, and learns the man is Richard Ranasinghe de Vulpian, an English jeweler working in Tokyo. Richard offers Seigi part-time work at his shop, and the two begin handling customers who bring in gemstones tied to personal troubles. Each case turns on the history and meaning of a particular stone as Seigi learns the trade at Richard's side.