Visit Out of the Blue(1959)

Original title: Besuch aus heiterem Himmel

The multi-millionaire John Underhower travels from New York to Bavaria, where he’s bought a castle. The reason? He wants to prove there’s ghosts in the old building. John represents himself as a poor circus performer to his unsuspecting cousin Hyronimus, who works as a tour guide at the fortress. And Hyronimus has no shame in pretending to John, that he’s the proud owner of the castle. This little game soon leads to a lot of complications.