Marlène, a young woman who has just arrived in Paris, meets a boy with homosexual tendencies, who during their first night of love behaves in a sadistic way. At first shocked by this attitude, she took a liking to it very quickly. From then on, in all of her adventures, she will always go further into masochism, forcing her partners to endlessly mortify her, alone or in a group. A real madness has seized her, which will lead her to the most extreme perversions.