The “Black International” did not hesitate to respond to Sergei Tarkhanov’s capture of the inventor of the “Wrath of Allah,” Professor Mashtakov. A full-scale military operation in Pyatigorsk confirmed it: from now on games with time and scientific experiments move into the phase of creating a superweapon—one that will lead to a war for world domination. Whoever will win is the one who dares to step beyond the threshold first. Beyond where? Into the past? The future? Into a foreign reality once seen by Tarkhanov—and for some reason strangely familiar. But will it not bring even greater disaster—for both the participants of the “expedition beyond” and for the world as a whole?