Seven hundred years ago, during a battle between Llewellyn the Great and King Edward I of England, a flying arrow killed a 14-year old boy. Llewellyn, son of Llewellyn the

Great, was trapped forever in the ruined castle on the wild coast of Wales.

He is rescued by David, a modern-day boy, and they become firm friends. David does not always appreciate having Llewellyn with him but having a ghost for a friend is certainly handy especially when they keep stumbling across crooks and evil criminals.

Together with Detective Chief Inspector Catrin Johnson and her young cousin, Jemma, David and Llewellyn travel to New York, London, Paris, Hong Kong, Sydney and the icy waters of the Arctic to save the world.

The Case of the Billion Dollar Threat is the first book of their adventures.