In this second addition to the Marmora Adventure Series, a boy named Francis arrives in Marmora for the first time only to find that Jenny and Draco, the Warder of the South March, have been captured by beings called Puddlefoots. Luckily, Kevin, Jenny's brother, had escaped capture. The wizard Sargon sends Kevin and Francis to rescue the two captives. Francis learns during their adventures that he has it within himself to face and solve difficult problems. The boys become great friends with each other and also meet a mermaid, an ancient turtle, a giant crocodile, and, of course, Shamus the leprechaun, who wants more chocolate.