On Sept. 21, 1929, each of the major Paris newspapers received a letter from a mysterious organization calling itself the Knights of Themis. The society had been formed, it said, to punish “swindlers, dishonest financiers and others of similar kidney” whom the authorities had failed to discourage.

First on its list was Joseph Eugene Clement Passal, a notorious confidence man who had just been released from Lille Prison after a paltry five-year sentence. Over the next several days, further letters told of Passal’s abduction and torture by a series of bizarre ordeals. Finally, on Sept. 26, he confessed the location of his ill-gotten loot, and his captors retrieved a box containing 10 million francs from the Forest of Essarts. Finding Passal hopelessly unrepentant, though, they resolved to kill him.

On Sept. 27 Passal’s mother received a letter in her son’s hand, confirming that he had been kidnapped, tortured, and sentenced to death. Six days later she received another letter, this one apparently from a repentant captor who thought his fellows had gone too far. He confided that Passal had been buried alive 75 miles west of Paris in a coffin that had been fitted with an airpipe to prolong his agony.

The authorities raced to the scene and found a freshly dug grave from which a tin airpipe protruded. In the coffin was Joseph Passal, dead. When detectives traced the purchaser of the airpipe they discovered Paris thief Henri Boulogne, who confessed everything. He and Passal had been cellmates in prison, and on Passal’s release they had rented a villa, where they had typed the letters and built the coffin. Passal directed his friend to bury him alive, expecting that the authorities would resurrect him and he could sell his story for millions.

The airpipe they had chosen was too small.