Follows the adventures of Sophie as she races against time to find the monster in the dungeon of Mystery Castle before the grand banquet. Readers are encouraged to help her on her way by solving amusing puzzles in Spanish. A Spanish-English glossary and pronunciation guide are also supplied. There is different coloured text for each language, with Spanish speech bubbles and a wordlist on each double page complementing the artwork. The book is based on the "Usborne Young Puzzle" series.