England, 1813: Lady Arianna Hadley acts the part of a French chef in one of London's aristocratic households to find her father's murderer. But when the Prince Regent falls ill after consuming Arianna's special chocolate dessert, she finds herself at the center of a scandal. It soon becomes clear that someone is looking to plunge England into chaos-and Arianna to the bottom of the Thames

Lady Arianna's gift of a rare volume of botanical engravings to her husband, the Earl of Saybrook, has something even more rare hidden inside-sensitive government documents which would mark one they hold dear as a traitor of King and country. To unmask the villain, they must root out a cunning conspiracy-armed only with their wits and expertise in chocolate