All grandmothers have secrets. Tom and Geri's grandmother, for example, was a secret agent when he was young, a master of martial arts, and an expert in firearms. Nickname: Mermaid. Lately
she mainly bakes pancakes at home for her grandchildren, for whom she goes to the fire if necessary. And he has to, and at gunpoint, because one of his grandchildren, Geri, is kidnapped. Is it a Mermaid?
can he still fight a group of mobsters as a pensioner? Fortunately, he is helped by his other grandson, Tom, who has fallen to his feet, and the Association of Seventh Graders. In fact, a former one
her secret service chief, the colonel, who is still in love with her, also appears.
The fun and exciting novel, which is a sequel to the books A bátyám zeni and A öcsém zeni, is an irresistible read for both children and adults.