"There were three of us in the marriage." Ellie can't push Princess Diana's infamous words out of her mind, except Ellie isn't dealing with a mistress, but with a matriach, and she can't decide which is worse... The Coopers were everything Ellie had always wanted. A large, loving family, parents Linda and Michael doted on their three children, and when Ellie married Dan, their eldest son, she was thrilled when they welcomed her in and treated her as one of their own. But Linda, who started off as the perfect mother quickly turns into the mother-in-law from hell, and once Dan and Ellie returns from their honeymoon and the Coopers' dysfunctions start to reveal themselves, Ellie wonders whether she's made a terrible mistake. Constant rows with her husband and a simmering fury with her new family, the arrival of baby Tom should ease Ellie's insecurities, but instead sets off a chain of events that threatens everything Ellie has always dreamed of...