Three (more) children spend their summer stumbling over an old mystery and hatching plots, but what passes the time for them is strictly tedious to readers. Observing tense family reactions to the news of tenants returning to a vacant house, Claudine, Paul, and Sophie can't get any straight answers so they check out old newspaper files at the library; before you can say crime passionnel, they dig up the wartime story of their French grandfather's prison sentence for shooting his neighbor Otto Brander, a German and his daughter Nicole's amour. The children and their new friend, the German's son, arrange a surprise reunion between Brander, a widower, and visiting Aunt Nicole, and a few days later secret wedding plans are revealed. Perhaps they've all been out in the Lot-et-Garonne sun too long for the plot twists are ludicrous (Grandpere, raging again, has a heart attack) and the adults have the insight of sausages. And the title's too marginal to explain.