Uncle Marin, the Billionaire (1979)

At a swanky hotel in a Black Sea resort, Gogu, one of the hotel employees, meets his uncle Marin, an Oltenian peasant who has come to visit. Gogu says he can sneak Marin into the hotel, as one of the rooms is empty awaiting the arrival of an American billionaire, Mr. Juvett. Marin is amazed by the revealing clothing worn by women at the resort, while the hotel guests are fascinated by his quaint peasant costume. In the hotel room, Marin is perplexed by the various gadgets. Meanwhile, the gangsters learn that Juvett has arrived at the hotel. Juvett is the father of the kidnapped girl, and is coming to pass over a million dollar ransom. A rival gang, who know about the kidnapping, plan to take the ransom for themselves. They follow Marin, believing him to be Juvett.

Unfortunately the movie Uncle Marin, the Billionaire is not yet available on HBO Max.