Content Warning: This section of the guide describes and discusses the source text’s treatment of child loss, death by suicide, gaslighting, and postpartum depression.

The novel opens in Adelaide Hills, South Australia, on New Year’s Day of 1959. Isabel Turner is hosting a lunch with her husband, Thomas, his sister Nora, and Nora’s husband, Richard. When Isabel overhears her children playing a game, she wishes for some peace and quiet, but she knows that Thomas wouldn’t approve of this thought; he has firm ideas about Isabel’s role as a mother and homemaker while he pursues his own business and travel endeavors. They have lived in the same house for 14 years, and Isabel is now nearly 38. Although she is surrounded by children, she still sometimes feels lonely. Now, she sees someone she assumes to be the mailman coming up the drive with a package, but she realizes as he comes closer that it is someone else.

Almost a year later, on Christmas Eve of 1959, a man named Percy Summer rides his horse in Adelaide Hills. Percy has ridden far in the heat, thinking about long-ago hot summers when he was bedridden with polio and discovered the wonders of literature.