'Whenever I find myself thinking in a brooding way, I must simply turn it off and think of something else. God forbid that I should become an eccentric.' Rachel Cameron is a shy, retiring schoolmistress, tethered to her overbearing invalid mother. Thirty-four and unmarried, she feels herself edging towards a lonely spinsterhood. But then she falls in love for the first time, and embarks upon an affair that will change her life in unforeseen ways.