The Bouvier-Sauvage family proudly traces its roots back to a long line of aristocrats. So when their only daughter announces she's marrying the son of a humble Peugeot dealer, the enthusiasm is limited. At the first meeting of the future in-laws, both sides quickly realize that they are worlds apart – not just in their taste in wine or cars. To make matters worse, the young couple has ordered DNA tests that reveal surprising facts about everyone’s ancestry. Oh la la, the mood threatens to collapse entirely, as the results could shake up family trees and put the entire wedding at risk.