Abi and Mark couldn't be prouder of their teenage daughters - but after an awful year, they dearly want to see their sweet, youngest daughter Beth with a smile back on her face.
So when she's paired up with glamorous Corinne in a French exchange, it's a relief to see the pair getting on so well.
But as Beth starts to misbehave, they begin to wonder how much they know about the girl they've welcomed into the heart of their family.
They're sure things will improve when they all travel to France for the summer. But under the hot sun passions flare, and tragedy strikes.
And they won't all make it out alive...
