Abi Holland considers herself lucky. She's happily married, and her oldest daughter, Eva, is all set for a place at a top university. It's her lonely, younger child, Beth, that she worries about. So when foreign exchange student Corinne comes to stay, it's a relief her daughter finally has someone to talk to. But when Beth starts to misbehave, Abi begins to wonder how much they really know about their guest. Because the Holland family have lots of secrets, and Corinne is quietly listening to them all. And once they come out, there's no going back...