When Christopher Brooke is arrested under Regulation 18B in June 1940, a slow process of personal disintegration begins, affecting his family irreversibly. Irish farm girl Mary Byrne is hired as housekeeper for the Brooke household and proves an acute observer of the daily lives of Cynthia Brooke and her three children. But when Mary is shockingly expelled from the house upon Christopher's release from internment, 15-month-old Katie -- conceived on a prison leave and now speaking from adulthood -- takes over as narrator. Moving from the pre-war political era of Ishiguro's The Remains of the Day, Mad Hatter delves into the wartime lives of Britons, and tracks them into the aftermath in a disturbing but ultimately transcendent story of a daughter's search for family history. Mad Hatter charts the gradual unravelling of a marriage and the tightening of its children in the devastation of post-war England as the story of the Brooke family moves inexorably to a tragic conclusion in which Mary Byrne is once again embraced by the family, but in a most surprising manner.