The plot is straightforward, however. Human beings have encountered what seems to be a living ocean on the planet Solaris, and singularly failed to make any sense of it at all. Explorers disappear, or return severely shaken by what they’ve encountered. Solaris seems to have the power to reach into the human mind and exploit dreams, desires and memories in disturbing ways.

After years of official dithering, the crunch comes when contact with the science team is lost. Psychologist Kris Kelvin is sent to the Solaris station (which seems to be floating in the upper atmosphere, rather than in orbit, though this is contradicted later) to investigate and report. He arrives to find the station in disarray; worse, an old friend he expected to enlighten him has committed suicide. The two surviving scientists are deeply strange. One, Snout, is friendly but twitchy, and there are signs that he has (impossibly) a guest. The other scientist, Sartorius, refuses to let Kelvin into his quarters at all, but he too acts as if he is not alone.

And there is someone else on board, a scantily-clad girl wearing tinkling jewellery who leads Kelvin to the freezer chamber where his friend’s body is preserved. The girl vanishes. A recorded message does little to enlighten Kelvin, but he is warned that it is dangerous to sleep. Sure enough, someone comes to Kelvin in the night. It is Hari, his wife. She killed herself years ago.

Kelvin’s response to the ‘fake’ Hari is to stuff her in an escape capsule and fire her into space. A second Hari returns, full of questions, and it becomes apparent that she is not the woman he lost but his memory of her. And, because he remembers how she died, this Hari must kill herself, over and over again. Solaris, the living ocean, can reach into the subconscious and create living images from it. (We never see what it has produced for Snout, and only briefly see Sartorius‘s creature - a dwarf. Neither visitant is explained.)

Sartorius has worked out that the emanations from Solaris can be dissipated by a burst of energy. However, this does not really offer a solution for Kelvin. The film comes full circle, apparently reprising the slow opening scenes at Kelvin’s father’s home. Tarkovsky offers us one last, startling vision of a man trapped by his past, unable to achieve redemption but incapable of moving on.

All very bleak, all very European. And that’s the point. American science fiction is often about pushing back a new frontier, overcoming challenges, and demonstrating what were once called manly virtues. This attitude is rooted in the history of the United States, which was built by frontier folk with a sense of their ‘manifest destiny’. Other cultures see things differently, and Russia is a land where the far frontier was for many centuries a place of punishment and despair, not heroism and opportunity. We may find no gods or demons in space but those we take with us, observes Tarkovsky, and who are we to say he’s wrong?

Solaris is a visually remarkable film, and offers a contrast to conventional space movies. Some scenes are breathtaking, as when Kelvin and Hari become weightless in a panelled dining room, complete with floating candelabra. This is science fiction for grown ups, offering philosophy instead of thrills. It is also a tragic love story. Some may find it intensely boring, especially in the opening scenes, but nobody said art had to be fun all the time.