At 29, Claire is full of the joys of life - that is, until her husband leaves her on the day she gives birth to her baby. With a broken heart, a beautiful newly born and an expanding mirror image, she decides to visit her eccentric family in Dublin. There she starts to feel better. So much better, in fact, that James is in for a surprise when he decides to slither back into her life....

Lola has every reason to be interested in who Paddy de Courcy is marrying - because although she's his girlfriend, she definitely isn't the bride. Heartbroken, she flees the city for a cottage by the sea. But will her retreat prove as idyllic as she hopes? Not if journalist Grace has anything to do with it. Grace knew Paddy a long time ago. But why can't she forget him?

Tara, Katherine and Fintan have been best friends since they were teenagers. Now in their early thirties, they've been living it up in London for 10 years. But what have they to show for a decade of hedonism? Sure, Tara's got a boyfriend - but only because she's terrified of spending five minutes alone. Katherine, on the other hand, has a neatness fetish that won't let anyone too close to mess up her life. And Fintan? Well, he has everything. Until he learns that without your health, you've got nothing....

June the first, a bright summer's evening, a Monday.... And into the busy, bustling homes at 66 Star Street slips, unseen, a mysterious visitor. As the couples, flatmates and repentant singletons of No. 66 fall in and out of love, clutch at and drop secrets, laugh, cry and simply try to live, no one suspects the visitor patiently waiting in the wings. For soon, as the light slowly fades to dark, everything is going to change....

They're a glamorous family, the Caseys. Johnny Casey, his two brothers Ed and Liam, their beautiful, talented wives and all their kids spend a lot of time together - birthday parties, anniversary celebrations, weekends away. And they're a happy family. Johnny's wife, Jessie - who has the most money - insists on it. Under the surface, though, conditions are murkier. While some people clash, other people like each other far too much.... Everything stays under control until Ed's wife Cara, gets concussion and can't keep her thoughts to herself.