Marc and Beatrice have been married for several years. While traveling in Italy where Marc has come to give a series of lectures, their two-year-old son, who has remained in Paris, is struck by a car and killed.
After that tragic accident, Marc lavishes more love on Beatrice than ever, giving her jewelry, furs and presents. But physically, he shows an increasing lack of interest in her and has relations with her lesse and lesse often.
Beatrice puts up with this in silence at first, then threatens to take a lover. Instead of being angry, Marc advises her to do so if that can make her happy. After much hesitation, Beatrice attempts the experiment, but is only disappointed.
During a hunting party, she runs into her friend Hélène and notices that Marc is not indifferent to the woman's charm. She asks Helène to seduce her husband to find out if he has an aversion to all women or only to his wife.
Hélène agrees to do so in her friend's
interest. With her, Marc succeeds in liberating himself. He confides in her and admits having an Affair with Norma, his secretary. But he assures Hélene that he is deeply in love with his wife. Hélène has hopes of restoring Marc to his wife. Beatrice discovers the Affair between Marc and Norma. Her anxiety is such that an insane scheme germinates in her mind.
She gets Norma to come to her home, plies her with drink and starts caressing her. She knows that Marc will come home and catch them at it. That is exactly what happens. At first Marc is excited by the spectacle of the two beautiful women, but he very quickly gets hold of himself. He is disgusted and tells Beatrice he is going away for a round-the-world series of lectures; he does not leave his desperate wife the time to reveal a very important secret.
A year goes by. One winter evening, Marc turns up at Hélène's place with his suitcases. She is not in. Marc wanders alone through her empty apartment. While leafing through a photograph album, he suddenly vivets his eyes on a picture o' Beatrice with their 3-month-old son.
Hélène comes home and finds Marc staring at the photo. She tries to comfort him but her charm no longer has any effect on him. Marc no longer reacts to anything. Hélène understands and explains to Marc that he suffered trauma after his son's death and gradually drifted away from his wife because of an unconscious fear of having another baby. She tells him that the picture he is pressing against his heart is not his dead son but a little daughter that Beatrice has had during his absence.
That is the secret his wife wanted to tell him when he refused to listen to her just before his departure. With this new child, Marc and Beatrice return to Italy where they last learned the death of their son and the presence of their little daughter restores their former love.