The River's End by James Oliver Curwood — Read

In the hall beyond the secretary's room Shan Tung waited. As McDowell was the iron and steel embodiment of the law, so Shan Tung was the flesh and blood spirit of the mysticism and immutability of his race. His face was the face of an image made of an unemotional living tissue in place of wood or stone, dispassionate, tolerant, patient. What passed in the brain behind his yellow-tinged eyes only Shan Tung knew. It was his secret. And McDowell had ceased to analyze or attempt to understand him. The law, baffled in its curiosity, had come to accept him as a weird and wonderful mechanism -- a thing more than a man -- possessed of an unholy power. This power was the oriental's marvelous ability to remember faces. Once Shan Tung looked at a face, it was photographed in his memory for years. Time and change could not make him forget -- and the law made use of him.

Briefly McDowell had classified him at Headquarters. "Either an exiled prime minister of China or the devil in a yellow skin," he had written to the Commissioner. "Correct age unknown and past history a mystery. Dropped into Prince Albert in 1908 wearing diamonds and patent leather shoes. A stranger then and a stranger now. Proprietor and owner of the Shan Tung Cafe. Educated, soft-spoken, womanish, but the one man on earth I'd hate to be in a dark room with, knives drawn. I use him, mistrust him, watch him, and would fear him under certain conditions. As far as we can discover, he is harmless and law-abiding. But such a ferret must surely have played his game somewhere, at some time."