Mia Channing appears to have an enviable life: a beautiful home, a happy marriage, a job she enjoys and three grown-up children to whom she's devoted. But appearances can be deceptive... When the family gathers for her son's thirtieth birthday, he brings with him his latest girlfriend, who, to their surprise, has a nine-year-old daughter. Then, before the birthday cake has even been cut, Mia's youngest daughter Daisy has seized the opportunity to drop a bombshell. It's an evening that marks a turning point in all their lives, when old resentments and regrets surface and the carefully ordered world Mia has created begins to unravel.