To celebrate Yves’ 50th birthday, his friends plan to take him to the sunny paradise of Paros in Greece. But due to a cancelled flight, the holiday will take place in a far less glamorous and much rainier destination: Yves’ family home in Brittany. During the vacation, their bonds are challenged by Antoine’s constant complaining, Yves’ pride, Baptiste’s superstition and Laurent’s jealousy of Jean-Mich’s perfect life and family. On top of that, Antoine’s supposedly harmless joke – offering Yves a DNA ancestry test – has unforeseen consequences…