Strange things start to happen when three siblings find themselves staying with their great uncle in his mansion in North Wales. Who is the ghostly boy who appears to them in the middle of the night? Why are they being watched by men in white robes? And who is the mysterious professor who tells them about the old legends and folklore of Wales? When an ancient power threatens their family, 12-year old David, his feisty sister Sian and resourceful brother Owen are caught up in a race across Snowdonia to find a powerful lost treasure. Can they solve the clues before a dark sect beats them to it?Illumination is in the spirit of classic children's adventure stories, but updated for a modern audience, both the young (9-12 years) and the young-at-heart (13-130!). It's a fast-paced, ripping yarn featuring storm-lashed lighthouses, speeding steam trains, ghostly encounters, mansions filled with secret passages, misty graveyards, pirate treasures, ancient shipwrecks, evil priests bent on human sacrifice, ruined castles, forgotten tomes hidden in musty libraries and much more.The book starts with this premise: what if the old Welsh legends are not just ancient myths; what if they're real, even now? Though its earliest inspiration might be John Masefield's wonderful 'The Box of Delights', ultimately it's also a respectful homage to the kind of children's fiction of the sixties and seventies which rediscovered ancient British history and presented it for fresh eyes, such as the works of Alan Garner and Susan Cooper, and television dramas like Brian Hayles' 'The Moon Stallion' and David Fisher's Doctor Who story 'The Stones of Blood'.