Pretty, intelligent and combative, Yoko Tsuno is an electronics engineer who always remains faithful to her values: loyalty, friendship and respect for life. In this volume, a megalomaniac businessman has stolen the artificial typhoon created by Yoko's father and intends to use it as a military weapon. Hundreds of lives are in danger. Yoko and Aoki, her teacher, eventually manage to neutralise the typhoon, but Aoki has to sacrifice himself in the process.