It is 1628, and Alexander Seaton's happily settled life as a university teacher in Aberdeen is shattered by the arrival in town of a stranger who looks like his twin and who carries a plea for help from Alexander's dead mother's family in Ireland. The family has been placed under a poet's curse, threatening death to various members. Elements of the curse have already begun to play out. Reluctantly answering the call, Alexander leaves his home and his beloved Sarah and travels to Ulster, to find himself among a family torn apart by secrets and long-buried resentments. In the course of seeking out the author of the curse, Alexander becomes deeply entangled in a conflict that involves fugitive priests, displaced poets, rebellious plotters and agents of the king. Confronted by murder within his family, he finds the lines between superstition and faith, duty and loyalty are becoming increasingly blurred, while his Scottish homeland grows ever more remote.