Worn out by twenty-five years of living together, the couple formed by Xavier and Sophie seem out of breath. And the least we can say is that Sophie's idea of inviting Adele and Alban, their upstairs neighbors, to dinner does not enchant Xavier! He criticizes them for a lack of discretion during their nocturnal antics, which are as frequent as they are wild. In contact with their neighbors with the most liberated morals, Xavier and Sophie will then confront their reality, before being pushed into a corner by a somewhat... indecent proposition.