FOUR COUPLES.Summer 1979. In the idyllic suburban neighbourhood of Ridgefield, during a scorching heat wave, four couples gather for their weekly dinner party.AN ORDINARY EVENING.When Frank Callaghan checks on the sleeping children, he finds an empty crib where his four-month- old daughter Megan should be sleeping. The party-goers swear they didn't see anything but each of them has something to hide.THE BEGINNING OF A NIGHTMARE.Forty years later, a stranger knocks at the Callaghan's door claiming to be Megan. The family are sceptical until they see what she is holding - the blanket she was wrapped in the night she disappeared. Where has Megan been all this time?And how well do you really know your neighbours?