The unravelling of a marriage, told in very precise language, through moments both real and imagined. We see what Jon's marriage was like, and we see what he imagined to have happened with his wife and her lover. Despite being loaded with sex, it is told in a rather numb, chilling way, so it's perhaps fortunate that the book is quite short. I found it difficult, and yet utterly compelling, as a tale of the painful failure of love.