Thirty years have passed since Investigator Shulgin tried to track down rare gemstones stolen during a major exhibition in the USSR. The case remained unsolved, the diamonds vanished without a trace, and Shulgin’s career went downhill. The keys to solving the high-profile robbery unexpectedly emerge in the novels of former Soviet chess player Angelina Goreglyad, who moved abroad in the late 1980s. After Angelina’s death, treasure hunters begin pursuing her relatives. Shulgin returns to an investigation that seemed hopeless. He has a chance to make up for his long-ago defeat, but above all, to cut off the bloody trail left by the diamonds.