In the year 2033, an apocalyptic disaster will befall the world. The Dark Ones, a race of mysterious aliens, will invade the planet and destroy everything in their path. The Earth will be left empty. The survivors will be few in number and will be forced to live underground in the city of Metro 20. They will have to fight for survival and fight to stay alive. The world has been turned into a dangerous place. The underground is a safer place to live, but it is still not safe. The Dark Ones have found a way to penetrate the underground. They have captured the world's leaders and are using them as a source of energy. The only way to stop them is to destroy the source of energy, which is the nuclear reactor.