Every Wednesday, French editor Pierre Brochand and some of his friends organize a very special dinner: a "dîner de cons" (Literally: "Dinner of idiots"), where whoever brings the dumbest guest wins. Desperate to find a suitable candidate for the week, Brochand invites a friend's recommendation: François Pignon, a taxman who build models out of matchsticks and seems like "a real winner". Unfortunately, Brochand hadn't exactly counted on the fact that on the evening of the dinner, he'd have thrown his back playing golf, his wife would have left him and he'd be stuck at home, alone with Pignon...