For 50 years, Douglas Latchford was the world’s premier expert on Cambodian art, supplying priceless statues to Western museums and rich collectors. But his fame masked a dirty secret. Douglas had colluded with the Khmer Rouge, a genocidal regime, to loot Cambodia’s entire cultural heritage. As the country descended into bloodshed, Douglas stole almost everything. A network of art world cronies were on hand to help him sell these blood statues, including a senior curator at the Metropolitan Museum in New York. When a band of art sleuths get on...