Nancy Drew's two-week tour of Japan has taken a sudden ominous turn. Checking into her Tokyo hotel, she watches in amazement as an elderly woman is surrounded by the police and accused of smuggling. The lady's souvenir vase has smashed to the floor, revealing hundreds of stolen pearls! Nancy's convinced that the woman has been set up and that now the members of her tour group are in peril as well-innocent victims of a far-flung criminal conspiracy! Meanwhile.... Frank and Joe Hardy are in Tokyo, working undercover at Amsa Inc., a huge Japanese electronics conglomerate. Someone has been knocking off cheap imitations of the company's high-tech line and selling them in America under the Asma name. When the Hardys hook up with Nancy, they discover that Japan is a land of exotic sights and extraordinary entertainments-Kabuki theater, sumo wrestlers, and lively nightclubs-but also a world of mystery and menace...