Grayson Hale, the most infamous murderer in Scotland, is better known by a different name: the Devil's Advocate. The twenty-five-year-old American grad student rose to instant notoriety when he confessed to the slaughter of his classmate Liam Stewart, claiming the Devil made him do it. When Hale is found hanged in his prison cell, officers uncover a handwritten manuscript that promises to answer the question that's haunted the nation for years: was Hale a lunatic, or had he been telling the truth all along?