Volcanoes all over the Earth are erupting as the 'dragons' within the Earth are being stirred by magic. As the Earth faces the catastrophic possibility of an eruption of its super-volcanoes, a criminal gang is hunting Myfanwy and a monster stalks Tom. Together they must find Merlin, who alone can quieten the earth, and they must get to him before those trying to kill him. They also need to sort out their relationship as the end of school is approaching and Tom is returning to Australia.

The Council of Nobles is openly trying to kill Tom and civil war is threatened in Annwn if Myfanwy will not agree to marry Alwyn apBryn. Torn between her love of Tom and her love for her people, she accompanies Tom into the high Himalayas, to confront a group of rogue monks who are steering an asteroid towards the Earth. There they will face magic, fighting monks, wild yeti and the consequences of violence and murder. It is a challenge designed to tear them apart and if they fail, millions will die. Yet the real challenge awaits them only if they succeed.