On a blazing hot day in late August 1914, 12 year old Mattie dances in the stream, spraying her little sister Evie with silvery showers of water. They have come here to cool off and to pick watercress for tea. They are unaware that their idyllic childhood in Suffolk is almost at an end, for as their mother says, 'all the world's gone mad.'
The girls will grow up to lead very different lives. Mattie is destined to travel far from home and to found a dynasty of strong-minded women like herself. Evie, in the role of family carer, still achieves a satisfying career.
But will the two sisters be reunited and a secret solved?