'Heirs of Promise', the second part in the gripping Z-Rod trilogy set in 6th century Scotland, intriguingly contrasts the lives of Pictish cousins striving to establish themselves – one as warlord, the other as a spiritual warrior. Styling himself on the boar, Oengus uses power and wily intelligence in a bid for independence from his overlord under the gathering gloom of war. Other shadows disturb: his ousted cousin, who bears the powerful 'Z-rod', still haunts; unrequited love for the inaccessible Alpia, consumes; and influential druids question his commitment to the volatile mother goddess. Abbot Fillan prophetically directs the exiled Taran to remake himself as a warrior-saint by acquiring nine graces. Propelled on an ominously named 'white martyrdom', Taran is tested by a series of quests and friendships to find his soul companion in his ultimate aim of 'bearing fire to the north'. The plot moves forward, with clever twists and dramatic moments that intrigue and shock the reader. The characters are sensitively depicted, their struggles laid bare, making for a complex story that the reader will follow with intrigue.