The events that overwhelm a middle-aged, seemingly happily married couple. The arrogant, bourgeois M. Hervey descends from a train into the teeming bustle of the city. While on his way home, he reflects on the sturdiness of his life: the success he has made of it, and the fortress of security he has built around himself. It is not long before his self-satisfaction is rudely shattered when he discovers a letter from his wife, Gabrielle, waiting for him on his sideboard. The contents of the message will crumble that security and plunge him into newfound feelings of vulnerability, abandonment and betrayal. Husband and wife find themselves engaged in a parry-and-thrust of emotions that change mid-sentence and stretch their ability to function and live in the same house.