A blind retired dentist has been run down by a logging truck on the street in Vientiane just opposite the post office. His body is duly delivered to the morgue of Dr. Siri Paiboun, the official and only coroner of Laos. At the age of seventy-four, Dr. Siri is too old to be in awe of the new communist bureaucrats for whom he now works. He identifies the corpse, helped by the letter in the man's pocket. But first he must decipher it; it is written in code and invisible ink. The dentist's widow explains that the enigmatic letters and numbers describe chess moves, but they are unlike any chess symbols Siri has previously encountered. With the help of his old friend, Civilai, now a senior member of the Laos politburo; Nurse Dtui ("Fatty"); Phosy, a police officer; and Aunt Bpoo, a transvestite fortune-teller, Dr. Siri solves the mystery of the note and foils a plot to overthrow the government of Laos.