Gordon and Sarah Rutherford are normal, happy people with successful, fulfilling lives. They have a son they adore, a house on the beach and a safe, friendly and honest community in a picture-postcard town on the Ayrshire coast. Until one day, Bonnie the lab comes in from the beach alone. Their son, Rory, has gone - the only trace left behind is a single black Adidas slider. Their lives don't fall apart immediately. While there's still hope (and no body) they dig deep and try to carry on. It's a process of abrasion - a wearing away of happiness and normality; a slow degradation, a gradual breakdown - until they'll never be the people they were before.