Some significant literary tropes featured in the novel include interstellar travel, "first contact", psychological fiction, a Communist utopia, and criticism of the capitalist militarism, which Lem himself characterized as an "extract of the times of Socialist realism".

Aboard a vessel called Gaia, 227 men and women leave the Earth for the Alpha Centauri system.

It was carrying still active biological weapons and nuclear warheads, which had accidentally left Earth orbit and got lost in space during the Cold War era, and the team destroys it.

Nevertheless, the crew of Gaia does not strike back, supposing the inhabitants of the planet mistook a peaceful landing for aggression.

Because at the time of writing cybernetics was a banned "bourgeois pseudoscience", Lem invented the term mechaneurystyka ("mechanheuristics").