Bradley Baker and the Curse of Pathylon

The first adventure in the series...
During the school summer holidays Bradley Baker visits his aunt and discovers a gold coin with magic powers.
"This is no ordinary coin," thought Bradley, as he is pulled down the plughole and sent spinning through time to the world of Pathylon...
A curse has been cast and the King imprisoned inside the Shallock Tower.
Bradley teams up with a band of renegades... can he influence the King's release, help lift the curse and escape from Pathylon alive?