Download The Christie Affair by Nina de Gramont PDF. In 1925, Miss Nan O’Dea infiltrated the wealthy, rarefied world of author Agatha Christie and her husband, Archie. In every way, she became a part of their life––first, both Christies. Then, just Archie. Soon, Nan became Archie’s mistress, luring him away from his devoted wife, desperate to marry him. Nan’s plot didn’t begin the day she met Archie and Agatha.