Villain or victim? Kate Grenville investigates a colonial cold case

Kate Grenville's new book, 'The Country Schoolmaster: A Mystery in 88 Letters' began with the discovery of an unassuming bundle of letters in state archives. On closer inspection, they revealed a curious tale of a rural teacher, Joseph Connor, accused of savagely beating his students. Was he a monster, or the victim of a small-town vendetta?