Natty and Sean Wainwright are happily married. Rock solid, in fact. So when Natty's oldest friend Eve Dalladay appears, just as their daughter collapses on a school trip in France, Natty has no qualms about leaving Eve with Sean to help out at home. Two weeks later, Natty finds that Eve has slotted into family life too well: Sean has fallen in love with her. He's sorry, he tells Natty, but their marriage is over. With no option but to put on a brave face for the sake of the children, Natty sets about building a new life for herself. And then she receives an anonymous note: EVE HAS DONE THIS BEFORE. DON'T LET HER TAKE WHAT'S YOURS ..