To the space station, whose staff has long and vainly been trying to cope with the mystery of the planet Solaris, covered by the Oceans, a new inhabitant comes, a psychologist Kris Kelvin, to understand the strange message coming from the station, and "close" it together with all its barren "Solaris stuff". At first, it seems that the few surviving scientists at the station have gone crazy. Then he himself becomes the victim of a terrible obsession: his former lover Hari, who committed suicide on Earth, come to him.