Merlin: The Hollow Queen

When Merlin agrees to help a young Druid boy, Daegal, he has no choice but to leave Camelot on a dangerous mission. And with the citadel distracted by the visit of the fearsome Sarrum of Amata, it seems that no-one will notice his absence. But as the sky darkens so do Merlin's suspicions - is there more to Daegal than meets the eye? And can a man as ruthless as the Sarrum ever really be trusted? Before long, the young warlock realises he's made a terrible mistake.