In fifteen-year-old Rex Marshall's mystical world, beings are classified by and can harness the powers of Earth, Air, Fire, Water, Light, and Darkness. When Rex, the rebellious son of an abolitionist councilman, impulsively purchases the freedom of Meenal, a peculiar blue slave, they discover a deep connection over one commonality: both don't know who-or what-they are. Rex and Meenal's journey of self-discovery and Rex's need to defend his birthright and inheritance takes them to the Saldur Empire, the country from which Rex's homeland, Maventa, won its independence-the same place his missing mother hails from. As Rex acts as ambassador between Maventa and the Saldur Empire, his connection to his mother becomes stronger than ever, and his origin becomes eerily clear. The quest to unearth their elements may prove life-threatening-or worse.