Nina is young, pretty and plump. Unfortunately her husband Gaspard only likes very slender women. To try to seduce Gaspar once again, Nina reluctantly accepts her new gift: a slimming treatment at Brides-les-Bains spa - the last resort for fat folk who have tried everything else.
At the spa, Nina gets to know Sophie, a beautiful Marseilles lawyer who wants to control everything, from her body to her heart.
She also befriends Emilie, a well-covered mom who proclaims loudly that "Big is beautiful," when her love life has stalled and her weight is beginning to cause her serious health problems. The encounter of these three personalities will unleash a tidal wave.