IN 1968 Jan Kadar was in the midst of shooting a movie when the Russian invasion of Czechoslovakia scattered his cast and crew. Kadar himself wandered over to America where he did a miserable adaptation of Bernard Malamud's Angel Levin. When the tension in his homeland eased, Kadar returned to Prague, regathered his company, and completed without the slightest visible ripple in continuity a film of extraordinary beauty and complexity.

Adrift centers around the tensions and confusion of a simple and moral man unable to deal with the temptation that befalls him. Since the story is told through his eyes, and because in his profound spiritual guilt he can no longer distinguish between the real and the fantasized, his shame and uncertainty color the movie. At least this much is clear: Yanos, an ordinary fisherman, saves from the river a naked girl. His wife revives her and easily accepts into the family this quiet, mysterious stranger whose past--even the attempted suicide--remains unexplained. Yanos, however, is powerfully attracted to her and is caught between his (to him) unacceptable desires and his consequent unresolvable guilt.

Kadar works with the absence of language to build an unbearable tension that his hero cannot dissipate. The girl, Anada, remains almost totally silent in Yanos' presence. She neither denies nor confirms the flirtation that his jealousy sees in all her movements near other men. When he discovers her alone, bathing nude, her actions stay neutral: she does not speak; her eyes reveal neither contempt nor attraction; she leaves the water and walks past him. Yanos is suspended in time, his sexual longing keeping him from turning away, his morality from advancing towards her. He cannot speak, for Anada has offered him no frame of reference, and his own conflicting feelings negate each other. She is an open vessel which is unsure how he should fill.

BUT THIS incident only probably happened. The narrative moves within the context of Yanos' explanation to his fishermen friends of Anada's return to the river and suicide. As Yanos recalls his increasingly dominant passion--his brusqueness dissolving into his kissing her, his resolve to flee melting into his buying her secret presents that she refuses, all his upright intentions leading to his sleeping with her--he cannot separate reality from his imagination's desires. When he recalls making love with Anada, she uses the same words as his wife. Has his imagination supplied that speech to make the act less immoral, or has he invented the whole incident, supplying the only words of response he knows?

The ambiguity highlights Yanos' tragic loss of equilibrium. His thoughts, he feels, have made him an adulterer. He no longer deserves his kind unsuspecting wife: his secret immorality estranges him from her. Just as the circumstances culminating in Anada's death can never be fully resolved. Yanos may or may not have caused through his neglect his wife's death to keep his timagined? sin from her. In the hazy world of sexual guilt, chronology has become unclear: only Yanos' tragic disintegration is certain.

Kadar owes many thanks to his cast, especially to his principal trio, for establishing a delicate imbalance of mood and then duplicating that same mood a year later. Rade Markovic as Yanos conveys the full range of his character's emotions and turns of personality without losing sight of the fisherman's basically uncommunicative nature. Milena Dravic portrays the wife as simple and innocent of her husband's lust without allowing her to appear to be simply stupid. Her pleasure in having a companion forms a perfect counterpoint to Yanos turbulent feelings towards the intruding girl.

AS ANADA. Paula Pritchett radiates a constant yet unmeditated seductiveness that drowns her rescuer in uncontrollable yearning. Kadar has exploited her dazzling beauty--and it is extraordinary--to project an indefinable combination of passivity and centripetal power. Reflecting the nuances and unsettling suggestions of the narrative, the camerawork moves from clear undisturbed landscapes to introspective shots of the mist-covered Danube. The symphonic soundtrack is occasionally over-dramatic, but mostly, it serves to reinforce Kadar's carefully composed ambiguities.

Kadar's exploration in Adrift of awakened sexuality and guilt is much more complicated (and demanding of his audience) than the painfully unswerving motif of complicity with evil he probes in The Shop on Main Street. Kadar has moved beyond a smoothly delineated story to create a disturbing aura of the off-balance and indefinite. The moral wrong against the Jews depicted in the older film may be more immediately dramatic, but the morally taboo of Adrift is ultimately more interesting. Kadar resolves none of the dilemmas that his movie raises; he merely suggests the universality and complexity of its problems. Uncertainty is at the film's center. Yanos questions himself so completely that he becomes unsure of the existence of the girl. In an age of doubt the threat of losing one's moorings is implicit in every variation of routine. Adrift is a magnificently crafted and disturbing reminder of every man's tenuous hold on the secure and the controllable.