'My father, that stern and upright man, was nothing but a swindler and a thief!' What is the matter with old Mr Jones? Endless footsteps and low groans can be heard from his room in the dead of night. Only his son William knows the a terrible secret: his father betrayed his business partner Mr Diamond, and swindled him out of a great fortune. William resolves to go to London, find Mr Diamond and make amends. But the murky big city, with its sinister characters and treacherous back streets, is no place for a boy of twelve. And Mr Diamond's own son is not the sort of person to forgive and forget. Danger and deceit lie waiting...