In a compartment of the Moscow-Novosibirsk train, a young physicist meets famous film actors. The conversation accidentally comes to Einstein, and the woman begins to explain to her fellow travelers what the theory of relativity is. The actors are incidentally on their way to the shooting of a film about physicists, but they do not understand the subject at all.

Научно-популярный фильм с элементами художественного кино, расскаэывающий о «теории относительности».