A boy becomes entangled in his family's mysterious past in this stand-alone sequel to Bloodline (2009). Despite his barbarous British parentage, Cai thinks of sophisticated seventh-century Constantinople as home, using his semi-magical powers of stealth and cajolery to gain renown as a thief. When betrayal sends him in chains to his parents' remote homeland, he is ensnared by the bloody heritage his father strove to keep hidden. Adopting the roles of slave, hostage, foster-son, witch, spy, warrior and even prince, Cai struggles to determine who he truly is and where he belongs. While the austerely elegant prose skillfully evokes two very different vanished worlds, readers unfamiliar with the minutiae of Anglo-Saxon history may find themselves lost in its convoluted politics; others may be disconcerted when memorable characters and intriguing plot threads are introduced only to disappear. No matter; the narrative is propelled by Cai's acutely observant voice and vibrant personality: cocksure, scheming, dishonest, sullen, passionate, painfully insecure and utterly irresistible. At its heart, this is the story of a boy's turbulent relationship with his father, torn between resentment and admiration, rivalry and respect, which renders the tale both as intimate as heartbreak and universal as hope. Grim, lyrical and unforgettable. (Historical fantasy. 12 & up)