Pierre Cohen, a sophisticated Parisian psychologist, goes to his brother's farm in order to protect it from very hostile local landowners.
Goubi, the simpleton of his village in the French Department Allier, has but one wish: to see Paris. One day, the truckers Grafouillère deposit a drunk Goubi in the biggest market of Paris (the "Halles"). The poor man is completely lost, but the meat merchant Dessertine takes him under his wings when he hears that Goubi was likewise 'raised by the State'...
In an elevator, a group of young people are in conversation...
