At just twelve years old, Tess Rainbow takes on the responsibility of caring for her younger brother after the loss of their mother, the wonderful Millie Mae. Then, one day in swirling smugglers' mist, a light plane, called The Spirit Of Millie Mae, crashlands near the Last Stop garage, Tess's home, on the edge of Romney Marsh. She helps to rescue the young pilot, Moray Tann, to the delight of Roma, her wayward elder sister. There is a long-standing feud between the Rainbow and Tann families but, despite this, Moray is a hero to Tess. So begins a dramatic relationship which lasts many years and is doomed to bring heartache. It will be a stormy path that Tess follows before, at last, the mystery unravels and she can find happiness.