Lydia Carlton is a fairy doctor, one of the few people with the ability to see the magical creatures who share our world. During one of her rare trips to London to visit her father, Lydia's quiet life is suddenly transformed when she is rescued from kidnappers by a mysterious young man!

Edgar and his small band must travel to the Isle of Manan, once home to the Blue Knight Earl. But the island is surrounded by merfolk, whose tragic songs cause rough seas and shipwrecks. And even if Edgar and his companions reach the island, they face death if it turns out he isn't a true heir to the Earl...