An affluent medical professor, Komiya, and his bossy wife, Tokio, are to look after Setsuko, their high-spirited niece from Osaka. Setsuko is a liberated woman who does what she wants, including smoking, even though she is a minor. On Saturday, the professor does not feel like going to his weekend golf game, but his wife packs him off anyway. So he leaves his bag at the apartment of his student Okada, and goes to a bar with a friend. Setsuko traces him there, and insists that he take her to a geisha house. When she gets rather tipsy, the professor calls Okada to take her home, while he sleeps at Okada's. The wife becomes suspicious of Setsuko when she sees Okada bringing her home, and also of her husband when she discovers that he did not go golfing.
工藤新一是中国著名的高中侦探。不幸的是，他在追捕一个黑衣犯罪团伙时被团伙成员发现。在被打晕后，他得到了一种神奇的药水，工藤新一又变成了一个孩子！新一找到了经常帮助他的阿里医生，医生为他量身定制了许多间谍武器。
东都总医院给一名困难患者服用了一种新药，该患者在三天后死于突发心肌梗死。患者的遗孀中原直美（由吉濑美智子饰演）悲痛欲绝。她认为丈夫死于医疗事故，因此她要求“勒索律师”Kojo和Ma（由Tomoto Ohmori饰演）对医院提出指控。
