An ancient legend says that Sir Roger de Flambeau hid a chest of gold before he died, but though many have tried, it has never been found. The only clue is a poem which refers to a mysterious Gargoyle Code. Green Group in Mr Fordham's Y6 class take on the challenge of finding the gold so that they can save their school from demolition. But there are many barriers to their quest, the head teacher, Miss Scratchard, the bully, Barry, and last, but not least, a Guardian Ghoul!