 Pierre Levasseur, an important CEO, is photographed with his lover, Elena, a world-famous model. In an attempt to salvage his marriage, he tries to convince his wife that Elena is not his lover, but that of François Pignon, a valet who was passing by and ended up on the photograph. To make his story believable, Levasseur then has to convince Pignon and Elena to move in together and to pretend to be a couple. Things get more complicated when this creates tensions between Pignon and his former flatmate Richard and his love interest Émilie, and when Levasseur s wife discovers the truth and decides to play games with her husband.