"1869. Tibet is closed to Europeans, an infuriating obstruction for the rapidly expanding British Empire. In response, Britain begins training Indians--permitted to cross borders that white men may not--to undertake illicit, dangerous surveying expeditions into Tibet. Balram is one such surveyor-spy, an Indian schoolteacher who, for several years, has worked for the British, often alongside his dearest friend, Gyan. But Gyan went missing on his last...