Knife in the Water (1963)

"Whether it be the clammy creepiness of suburban Satanism shocker Rosemary's Baby or the cloying seediness of nilhilistic noir Chinatown, Roman Polanski has a gift for conjuring an unsettling atmosphere. Knife In The Water, his feature debut and only Polish film, is no exception. It's a slow-burning exploration of jealously, spite, and middle age - set almost entirely within the confines of a small yacht."
Co-written by Polanski, Jakub Goldberg and Jerzy Skolimowski this remarkable directorial debut won Polanski worldwide acclaim, a place on the cover of Time, and his first Oscar nomination.
I wanted my first feature film to be cool, brain-worked, construed, and precisely, almost formalistically constructed. It was to resemble a classical thriller: a married couple take on board of their yacht a passenger who then vanishes in mysterious circumstances. My idea from the very start was to show a conflict-rich interaction between characters confined in a limited space. (Roman PolańskiRoman. Warszawa 1989)

Andrzej, a sports journalist, and Krystyna, his wife, are driving in their luxurious car for a holiday in the Masurian Lakeland. On the way they give a lift to a young hitchhiker.

 At once both fascinated by the young man’s vitality they invite the hitchhiker to join them for a day and night on the water. 
Shortly after tension gradually starts to build between Andrzej and the hitchhiker as they compete for the attentions of Krystyna.
The rest of the film documents this competition that ensues between the two men.
However, the struggle is not merely between the two men, but also between the men and the woman. In the final section of the film, Krystyna refuses to remain a witness or prize  and instead becomes an active participant in the events that follow. With the knife in the water the climax begins and neither of the man is unable to assert his power over the boat, the woman or each other.

The film started a true media storm in communist Poland. Polanski was attacked for snobbery, yielding to Paris fashions, superficiality. Many opponents of the picture found the journalist's financial status particularly painful. The supporters pointed out utter materialism of the aspirations of the characters and of their relationships, and the bogus rebellion of the boy, his set of values being in no way different (Małgorzata Hendrykowska Kronika kinematografii polskiej 1895-1997 / A Chronicle of Polish Film-Making 1895-1997, Poznan 1999).

Polański's film was arguably the first attempt of the Polish film-making to come out of the closed circle of the historicism of the 'Polish school' with its fixed repertory of topics, complexes, traumas and individual and collective obsessions. In this sense it is a completely new and fresh thing, unknown in our post-war cinema. No Polish director had ever talked like that. (Marek Hendrykowski Kwartalnik Filmowy, 1997)