After the dual disasters of nuclear war and the "Essence Virus", the old human civilization collapsed on Earth. The world is divided by radioactive dust, mutated life (called "aberrants") and out-of-control intelligent machines. The timeline is in the "New Era", and survivors have built ramparts (large survivor cities) and settlements on the ruins. A modern man awakened from the "cryo-sleep chamber" of the old era. The game starts in an abandoned underground research institute. He knows nothing about the new world, but he possesses rich scientific knowledge and fighting skills from the old era.
