One day in 1948, a well-dressed, middle-aged man walked into a branch of Tokyo's Teikoku Bank wearing the armband of a municipal official. Claiming that he was a city health inspector, the man ordered the bank manager to summon all his employees so that he could give them a dose of antidysentery medicine. The employees gulped the potion, then collapsed in agony. From the open vaults, the medicine man grabbed about $185 in cash and disappeared into the street. Behind him, twelve people lay dead of cyanide poisoning.
Then began the hunt. From witnesses, artists drew a composite picture of the...