Ellie has always disliked the local big estate agent - aka Great White Shark - and is distressed when her daughter Diana announces that she is carrying his child and about to become his fourth wife. But Ellie is soon drawn into the family circle when one of the Hooper children dies in their private gym and another succumbs to a peanut allergy. The police want to write off the deaths as accident and misadventure, but Ellie believes someone is targeting members of the Hooper family. Surely Diana wouldn't . . . or would she?