The story follows the adventures of two American sisters, Rosalie and Bettina Vanderpoel, as they travel to England to visit their married sister, Lady Anstruther. Lady Anstruther has married a wealthy English nobleman, Sir Nigel Anstruther, and is living in his ancestral home, the crumbling and decaying Mellowdene Hall.While in England, Rosalie and Bettina discover that Lady Anstruther's marriage is not as happy as it seems. Sir Nigel is an abusive and controlling husband who has isolated his wife from her family and friends. The sisters are determined to help their sister escape from her unhappy marriage and restore Mellowdene Hall to its former glory.