Willy Vanderbrook, a brilliant Franco-Belgian who has become a citizen of the world, applies for a job as a concierge in a grand Parisian palace.
He is welcomed by a childhood friend, Serge Luyperts, a disillusioned lemonade man who shelters his ex-brother-in-law, Frank Vrut, a Walloon independence fighter who is nicely psychopathic. Willy’s candidacy – rejected for Belgianness – will force him and his compatriots to an absurd and “royally” revanchist imposture…
Pretending to be the heir to the Belgian crown, Willy and his gang set off a series of joyous outbursts in the five-star hotel, which quickly attracts the attention of Jessica, a professional schemer. But, thinking to seduce the future “king of the Belgians”, she is going to rub up against a stronger one.
This burlesque detonator then leads the trio “made in plat pays” in a more consequent and more hazardous swindle.