The plot of the book "Лунный мальчик" (Lunar Boy) by Yuriy Kovalev revolves around the story of a young boy named Ivan, who lives in a post-apocalyptic world where human civilization has been destroyed by a devastating war. The story takes place in a small community of survivors who have taken refuge in an underground bunker, where they struggle to survive in a harsh environment with limited resources. Ivan, who was born in the bunker, has never set foot outside, and his only connection to the outside world is through the stories told by the other inhabitants of the bunker. He is fascinated by the technology that once existed above ground and spends most of his time studying the old books and trying to understand how things worked before the war. His obsession with technology leads him on a journey to discover the truth about the past and the possibility of rebuilding society.

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