Travelling to the northern state of Wisconsin, Lucky Luke finds a population deeply depressed by a beer shortage that has caused all saloons in the area to close. Desperate, the inhabitants of New M?nchen beg Luke to talk to the brewers of Milwaukee. But the cause of the shortage is a strike, and the cowboy is more used to chasing outlaws in the Great Plains than to forcing negotiations between unions and bosses in a city where the first skyscrapers are already sprouting ...