In the summer of 1913, George Sawle brings his Cambridge schoolmate—a handsome, aristocratic young poet named Cecil Valance—to his family’s home outside London. George is enthralled by Cecil, and soon his sister, Daphne, is equally besotted by him. That weekend, Cecil writes a poem that, after he is killed in the Great War and his reputation burnished, will become a touchstone for a generation, a work recited by every schoolchild in England. Over time, a tragic love story is spun, even as other secrets lie buried—until, decades later, an ambitious biographer threatens to unearth them.