This unpretentious little comedy is much fun to Watch;it takes place during the 1937 world fair in Paris and so it prevents the movie from falling into filmed Theatre De Boulevard .
Two families meet at the fair: the Belgian one has an a son,Arthur,apparently a simpleton (but smarter all in all than he looks) ,played by Francis Dupret,who resembles a Young Fernandel..The French one comes from Marseille and the father (Charblay whose playing was certainly influenced by that of Raimu) is under a talkative colorful matron's thumb.They have a daughter,but she is rather bland ,and Arthur finds Gaby ,a shady girl he met in the station,more attractive .
Unfortunately ,Gaby is a gangster's moll ,and her lover wants to use her to latch onto the naive families' dough.Then begins a far-fetched pleasant story involving a duke whose desirable mansion is used as ...the American embassy,a wizard who predicts great things ,a would be ambassador who could keep the suckers' money in his safe .
Add the so-called "Excellency" who speaks delightful Franglais ,the Belgian ,their accent and their gibberish,the Marseillais who can't even recognize pastis,the most famous drink of their hometown....and you've got a funny film.