Amandine is twenty years old, the most beautiful buttocks in Paris, and unfortunately a very ugly nose, which forces her in her profession of model, to pose only from behind. Trying in vain to save money that her sister Joëlle constantly borrows from her, she will finally be reimbursed and will thus be able to afford aesthetic surgery and become a lovely cover girl...

Clement Mastard is the head of a leading journal dedicated to extravagant vaudeville. An unexpected contract requires him to reconnect with his former headliner Celia Bergson part to try to avant-garde theater. It is through this that he met Johann Sebastian Bloch, misunderstood musician who cause the loss but the side which Mastard, the man without scruples, to humanize and eventually produce a real masterpiece, the Missa Solemnis