The Russian Triptych

The first novelette: The Russian Triptych is about Victor, a German collaborator in WWII. After serving his term in the GULAG, he lives in Siberia. He shoots a geologist who reminded him of a boy he had left half-dead at Babi Yar. In prison he kills his cellmate, escapes and flees to Leningrad, where he blackmails another former collaborator. The story has a new continuation set in USA. The second one: A Confession During the Last Week of Life is about a White officer who infiltrates into the Soviet Cheka after 1917 revolution and becomes a high rang KGB-ist influencing the fate of Russia.
There are number of other short stories in the book