Before World War II

In 1933, the Polish Cipher Bureau even gets access to the Enigma operating procedures that are used by the German Army. Hans Thilo Schmidt, a German playboy working at the German Cipher Office, is in need of money and sells infomation to the French secret service. The French, who gave Schmidt the codenameAsché, pass it on to the Poles, who can now reconstruct the machine.

From 1933 onwards, the Poles intercept and decrypt a significant portion of the German radio traffic. In 1938 they see an increase in the number of messages sent by the Germans and it seems clear that Germany is preparing for war.

Unfortunately, their luck is about to change. In late 1938, the Germans discover the mistake of the doubly-enciphered message indicator and change the message indicator procedure. They also add two extra wheels (IV and V) to the existing three, which multiplies the maximum number of possible settings by a factor of 10.

In the meantime, the Poles have built their own equivalent of the Wehrmacht Enigma with a plugboard added towards the rear. The wiring of the two additional wheels is soon recovered by Rejewski and suitably wired wheels are added to the Polish Replica. With the war imminent, the Poles start looking for ways to get their knowledge out of the country before it is too late.


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