A man and a woman meet in a train.  The woman is a Russian countess from St. Petersburg, a very beautiful aristocrat, who's traveling to the south of France for health reasons.  She is reluctantly leaving behind in Russia a husband who doesn't love her anymore.

Suddenly a man bursts into her compartment.  Since this is a region where there are a lot of brigands and thieves, and since she's carrying a large sum of money with her, she is of course very frightened.  The man she sees, however, does not look like a bad man. He's handsome, cultivated, dressed in formal evening wear, and his hand is injured.  He immediately tells the countess not to be afraid of him.  He's in danger and he needs help.

The countess helps him.  She passes him off as her and sends her real servant Ivan back to St. Petersburg.  But she attaches a single condition to what she's doing: the man will never ever say another word to her again. He accepts the condition and they continue on the trip to Menton, in the south of France.

The years go by and the woman grows old.  She continues to be sick. The man doesn't speak to her, but he doesn't leave her either.  He watches over her from a distance, adoring her from afar, without ever coming close to her.  He often asks her doctor for news of her.  She knows he's there, too.  He is in love with her, and she with him, but they never speak to each other.

People often ask the lady why they don't speak to each other, and she replies that that would spoil a perfect love. They carry on like this until the countess'  death.  That day, the man begs the doctor to be allowed to see the body.  He holds his beloved's hand and cries desperately, then goes away.

The main question that this story raises is: did these two, who seemed to be passionately attached to each other, even though they hardly  knew each other, love each other?  Was it really love, or was it only an illusion of love, the romantic idea of love?