One of the longest fictions he had yet attempted, the smoothly narrated story shows that James was rapidly maturing in style and technique.
Superficially, Madam de Mauves leads a happy life with a wealthy and "irreproachably polite" husband, but Longmore soon becomes convinced that she harbours a deep sadness.
Longmore agonises over how to proceed; he finds it difficult even to decide to continue his daily visits: "His presence now might be simply a gratuitous cause of suffering; and yet his absence might seem to imply that it was in the power of circumstances to make them ashamed to meet each other's eyes."
Eventually he visits Madame de Mauves, who rather cryptically asks him to confirm her very high opinion of him by doing the proper thing: "Don't disappoint me.
After much reflection, Longmore concludes that she wishes him to voluntarily break off contact — to do so not because she has dismissed him, not because there has been a 'scene', and not with any promise of meeting again in future, but simply because it is the honourable thing to do.
The Comte had indeed repented, and had begged his wife to forgive him, but Madame de Mauves had remained as stoically unforgiving as she had been stoic in her resignation: "[H]e fell madly in love with her now.
In this story James' international theme takes a tragic and even perverse turn, as the marriage of a somewhat puritanical American woman and an easy-living, pagan Frenchman leads to despair and suicide.
Whether an affair between Longmore and Euphemia (suggested by the amoral Richard and his equally cynical sister Madame de Clairin) would have made any difference is doubtful, but things couldn't have turned out much worse under any circumstances.
In that much later novel, a marriage similar to the one in Madame de Mauves is saved by the kind of careful diplomacy that neither spouse in the earlier story is capable of.
Others maintain that such a man could easily sicken of life and decide to end it all, but have doubted that he could ever have repented and asked Euphemia's forgiveness in the first place.
Although the believability of the story's conclusion is somewhat in doubt, many critics agree that James narrates the tale in a more assured and masterful manner than he had demonstrated in any of his previous fictions.