1972. Gilles and Christine are attractive, sexually active teenagers from unstable homes. When they do some shop-lifting together she is arrested, but he gets away. She escapes from a mental institution and meets him at an abandoned house in the country, where a large group of rebellious teenagers are having a wild, all-night party. As the party is winding down, Gilles and Christine escape even deeper into the countryside, searching for a commune where artists are said to live without electricity or running water.