The surface dwellers live in a world of eternal twilight where they struggle for existence against mutated creatures and each other. The underground people are safe but their world has also changed They have become slaves to the masters of the underground empire who rule them with an iron hand. The main character is a young man from the surface who falls into the underground world and becomes the key figure in the battle between good and evil that will decide the fate of humanity. The plot of the book 'Аванхальм Чужая кровь' (Alien Blood) by Николай Клюев is a gripping and thought-provoking tale that delves into the evolution of technology and its impact on humanity. Set in a post-apocalyptic world where a nuclear catastrophe has devastated the Earth, the story follows the journey of a young man named [Protagonist Name] as he navigates the challenges of this new world. The book begins with the protagonist's journey to find his place in a world that has been forever changed by the disaster. He discovers that the Earth has recovered, but everything is different now. The seas have dried up, plants and animals have evolved, and the cities of the former civilization have gone underground. The world above ground is perpetually shrouded in twilight, and the people there are fighting for survival against mutated creatures and each other.

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