Recognized by many critics as the "second best 'first' film" after Orson Welles' Citizen Kane, Knife in the Water employs many of Polanski's trademark stylistic elements. A claustrophobic horror-suspense drama with a cast of only three, Knife in the Water takes place almost entirely on a boat in the water, and deals with jealousy, deception and subtly class struggle. Self-centered Andrzej and his wife Krystyna while riding towards a lake for a boat ride, almost run over a young and buff hitchhiker who they invite over to the boat. Out of jealousy, and to patronize the young men, Andrzej constantly belittles the young hitcher, all the while maybe deliberately ignoring his wife's attention drifting towards this hunky stranger. Tension rises, a fight breaks, and the young stranger falls off the boat into the water with a knife in his hand.

The much insinuated class struggle in the film was incorporated due to the pressure exerted by the then communist rule of Poland. Also worth noting is that the young hitcher was dubbed by Polanski himself. Shot in 1962 with a fairly amateur cast of only three following a series of highly acclaimed shorts, Knife in the Water is still contemporary with its detailed character analyses, cold psychological tension and high contrast black and white images. The victorious challenger of the film nominated for the Best Foreign Language Film Oscar was Fellini's 8½.