Kurt Frederick Ludwig - The Search For The Spy Ring

The Search For The Spy Ring

Authorities in both the U.S. and the United Kingdom were by that time aware that a spy ring was operating out of New York City. The first break came when British Imperial Censorship in Bermuda, run by the British Security Coordination (BSC) — actually a cover for the Secret Intelligence Service — intercepted a letter written to "Lothar Frederick" and signed by a "Joe K". As it was known that "Lothar" was an alias used by Heydrich, a watch was set for any letter with the Joe K signature. Subsequent letters from Joe K were intercepted, their contents read and recorded, and the envelopes so carefully resealed that their recipients would not detect any evidence of tampering.

Joe K had shown up as the signature on many letters sent to accommodation addresses. In March 1941 BSC chemists detected secret writing in a Joe K letter; the secret message referred to a duplicate letter sent to "Smith" in China. The BSC mail-intercept operation was run in coordination with the FBI — even though J. Edgar Hoover, the Director of the FBI, and William Stephenson, the head of the BSC, did not get along. The FBI was able to trace the Smith letter and found that it contained a plan of U.S. defenses in Pearl Harbor.

Despite this break, they were still in the dark as to who were involved in the spy ring, until an unexpected event took place that led eventually to its unravelling and downfall.