Science fiction film with a mundane love story: Eight space ships have disappeared without a trace. Maria, the daughter of the professor at orbital station "Margot" stays on one space ship, while cosmonaut Dan who is in love with Maria sits on another space ship. Dan receives the order to block the way for a third space ship that tries to enter the "Margot" station despite a ban. Maria′s space ship follows him. On board of the orbital station, Dan and Maria meet again, and the secret of the eight space ships that had been tracking an unexplored light signal is disclosed.