January, 1931. Mounted Constable Bowler Brown, ex-light-horseman from the Great War, is stationed in Kularook, a small South Australian town. Then Agatha, who two years before ran away from her stifling marriage to Lew Benson, returns to him. As the summer heats up Bowler tries to keep the peace between factious locals while Agatha, on the isolated farm, struggles to retain her sanity in the face of Lew and his family's hostility. An old friend tries to help, but instead raises tensions to dangerous levels. When tragedy strikes, Bowler has to find out what really happened. Was it murder-plus-suicide? Were four shots fired from Lew Benson's rifle? Or were there five? And who is trying to kill Agatha?