In Norwegian city Bergen fully ordinary Norwegian family lives to itself: mother, dad, six-year-old Martin and his senior sister Matilda. But all changes, and life is suddenly filled with adventures, when to them arrives to stay grand-dad Oscar, that children never saw before. Oscar not for nothing was nicknamed by the Chocolate grand-dad, in fact he is frightful сластена and can not live without candies and chocolate. And yet he - want believe, and want it is not - able to walk about ceiling, here such unusual grand-dad! Simultaneously with Oscar to Bergen arrive sister Паульсен, three harmful enough ladies that, vice versa, can not stand sweet and dream, that all cakes and pastries in city became bitter or salt. Why does it need them and succeeded to blow off them the annual municipal fair of sweetnesses, or someone will prevent to their insidious plans? What did this keen detective history make off? Read a book - and know.