England 1912. Danby Hall is the only home Lady Cecilia Bates has ever known and she can't imagine life anywhere else. But now, with an agricultural depression sweeping the countryside, the Bates family's possession of the hall is in peril. A possible solution arrives in the form of American heiress Annabel Clarke. The Earl and Countess of Avebury are determined that Cecilia's brother, Patrick, will win Annabel's hand in marriage - and her fortune along with it. But when a guest dies after sipping from a glass meant for Annabel, it's clear the Bates have a more poisonous problem on their hands.