Andrei Tarkovsky's adaptation of Stanisław Lem's novel. The Soviet response to 2001: A Space Odyssey, and one of the few science-fiction films interested in interior rather than exterior space.
Earth, near future. Kris Kelvin, a psychologist, is dispatched to the space station orbiting the planet Solaris. The mission has been studying the planet's surface — a sentient ocean that scientists believe is alive but whose form of life cannot be communicated with — for years. The station's three remaining crew are exhibiting psychological symptoms that the agencies on Earth cannot explain.
Kelvin arrives to find one crewmember dead by suicide, the other two avoiding him. He soon experiences what the others have been: the ocean produces 'visitors,' physical reconstructions of significant figures from the visitors' deepest memories. Kelvin's visitor is Hari, his wife who killed herself ten years before. The film tracks Kelvin's months on the station as he tries to understand whether Hari is in some sense his actual wife restored, a planetary projection of his memory, or something else entirely.
Solaris was, in some sense, Tarkovsky's deliberate response to 2001: A Space Odyssey (1968). Tarkovsky had seen Kubrick's film and was critical of what he considered its emphasis on external science-fiction iconography over interior psychological substance. Solaris is, by structural design, the inverse: minimal external science-fiction iconography (the space station interiors are recognisably 1970s Soviet design with minor extrapolation), with the film's substance entirely in the characters' interior states.
The argument the film makes is that genuine first contact with an alien intelligence would not produce the kind of grand exterior spectacle that Kubrick depicted. It would produce a forced encounter with the human interior — the parts of ourselves we cannot fully access, the dead we cannot let go of, the memories whose physical reconstruction we cannot interpret. The ocean of Solaris does not communicate in the conventional sense; it produces effects in the human visitors that the visitors must, in some sense, learn to read.
The film's most-discussed sequence is the four-minute Tokyo freeway tunnel sequence that occurs roughly forty-five minutes in — the scientist Berton's car passes through an extended highway tunnel system, with the camera mounted on his car. The sequence is, on the surface, narratively unimportant; it depicts the journey from a meeting back home rather than significant plot.
What the sequence is structurally doing is establishing temporal patience. Tarkovsky is teaching the audience how to read the rest of the film. The freeway sequence is the audience's training for the slower sequences to follow. Many subsequent directors have cited the sequence as foundational. The opening highway sequence of Denis Villeneuve's Blade Runner 2049 (2017) is, in some sense, a direct citation.
Stanisław Lem, the Polish author whose 1961 novel Solaris was the source, openly disliked Tarkovsky's adaptation. Lem's complaint, articulated across multiple interviews and writings, was that Tarkovsky had centred the film on Kelvin and Hari's emotional relationship while the novel's emphasis had been on the philosophical problem of communicating with an alien intelligence that does not share human cognitive structures. The two writers exchanged unfriendly letters during production.
Both positions are defensible. Lem's novel is more rigorously science-fictional in its treatment of the alien intelligence; Tarkovsky's film is more emotionally substantial in its treatment of the human protagonists. The 2002 Steven Soderbergh adaptation (with George Clooney as Kelvin) attempted a middle position; many critics consider it the weakest of the three Solaris versions. The 1972 Tarkovsky and the 1961 Lem are, in the end, two distinct works on the same source material.