Adapted from the internationally praised and bestselling novel, ONE DAY charts an extraordinary relationship. After only one day together in 1989, Emma Morley and Dexter Mayhew cannot stop thinking about one another. Over the next twenty years, key moments of their relationship are revealed on the same day - July 15th - of each year. Dexter and Emma experience friendship and conflict, dreams and missed opportunities, laughter and tears. As the true meaning of this one crucial day is revealed, they must come to grips with the nature of love and life itself.