en Cuevana 3. After an accident at a compressor station in Kazakhstan kills her husband, Ainur, a young Kazakh woman, travels to Russia to find Andrei Artamonov, her husband's former university classmate and best friend. Together with Ainur and the head of the station Lykov, Andrei has to find a solution to a problem that failed his university project many years ago and make what might be the hardest choice of his life.