Published in Detective Comics #12, February, 1938, 4 pages.
On their first day in Paris, Bart Regan and Sally Norris are ordered to the Secret Service's office there where they are given their next mission. A man named Rene D'Arnot is "suspected of being a paid assassin of international gangsters, responsible for the death of many American diplomats". The order is that "this man must not live to carry on his reign of terror".