In 1972, Karl Lagerfeld is an unknown 38-year-old designer of ready-to-wear fashion, largely unknown to the public. His encounter with the young Jacques de Bascher, an ambitious and seductive dandy, changes everything. Karl is finally ready to go up against his friend, haute couture genius Yves Saint Laurent, and his formidable associate, Pierre Bergé. Glamour, ego battles, extravagant celebrations and destructive passion: Witness how Karl Lagerfeld became a legend.

This is the story of three men in their 40s, confronted with their limits and three younger women who are usurping the old order. They are all gathered under the sun in Ardèche to shoot a film that will not happen.

Guillaume Canet is told by a young co-star that he's no longer Rock'n' Roll and can't sell films anymore. He then tries to prove her wrong and gets help from his girlfriend, Marion Cotillard.