Oliver Evans spent his youth spinning one tall tale after another until it got him over his head in trouble. Returning as an adult to his grandmother's cottage in Aberdaron, Olly is determined to put his past behind him and settle down. But the misty Llŷn Peninsula hides dangerous secrets. Olly is torn between the Longing, a powerful force driving him away from the only home he has ever known, and the growing conviction that the merman prince of his childhood make-believe is real--and in desperate need of Olly's help.
There is more truth in Olly's stories than he realises. If he is to have any chance of righting past wrongs and rescuing his prince, Olly must navigate the truth in his old stories and discover the magic right in front of him. But Olly has a powerful enemy on the Llŷn, an ancient king who would like to end Olly's story-telling permanently.