Silicon life forms, locked in the magmatic worlds of the Altair system, want to make their own colony out of the Solar System, burn it in thermonuclear fire and turn each planet into a kind of vulcanizing Titan. The siliconoids have studied earthlings well: these ugly and fragile protein lumps do not deserve to exist in space, full of radiation, extreme temperatures and electromagnetic fields. And the only thing that can stop them is the Lenin's Head Nebula.