Anne, a thirty-year-old stage actress, has been living for seven years with Julien, a small-time photographer who taints her life with his own mediocrity. She would like to leave him but is unable to tell him. Anne has a sister, Simone, who runs a fashion house in London and that she admires and envies for her elegance, her self-assurance and her success. When one day, Simone comes to Paris, she tells her sister she cannot stay as long as expected, she gives her some money and goes away. Without knowing the reason why, Anne puts up at the luxury hotel where Simone was supposed to stay and starts behaving like her. For three days, she will not be the meek Anne anymore but the triumphant Simone. Once the crisis is over, she comes back home as Anne again, but a new Anne who has succeeded in gathering enough strength to confront Julien and to tell him she is a free woman and she does not want him any longer.