Sacha is a real seducer, a man with no ties or emotional or professional. Charlotte is a modern and independent woman, but barely has time to care for their three children. While Sacha and Charlotte are, at first glance, two incompatible beings, when they meet soon discover that they are quite complementary and need each other.

In 1924, Simone de Beauvoir, a girl with polished appearance, prepares for her final examination in philosophy and meets Jean-Paul Sartre. He seems to know her true personality and considers her the only woman worthy of his intellect. Their chaotic love serves as the premise for her magnum opus The Second Sex.