A dragon egg was stolen by elves and lost in Nant-y-Ceirw 500 years before. Now it's hatching, in a world where it doesn't belong. The town and the wood will be destroyed and the dragon itself will die, unless David, Eleri, Brynmor, Tati and Daio, can save them.
But Time and humans mean nothing to elves. They'll do anything to cover up the theft. The bwganod and the children are up against cleverer, more powerful enemies than any they have faced before. Their whole world is at stake.
All they have is their own courage... and a Moon-Horse.