Erich Zimmerman was a German general and a loyal member of the Nazi Party, guilty of category three hate crimes. In 1938, he was cornered by the Teselecta in an office in the Reich Chancellery in Berlin. The robot assumed his shape and appearance before the terrified General's eyes. The Teselecta miniaturised Zimmerman and transported him inside itself. Upon discovering his identity and political affiliation, the crew abandoned him to be killed by the antibodies.
The Teselecta, disguised as Zimmerman, made its way to the office of Adolf Hitler, where it attempted to punish him. The Fuhrer was saved by the sudden — and coincidental — arrival of the TARDIS through his office wall. After encountering the time travellers and receiving scrutiny from the Doctor for their performance, the crew of the Teselecta opted to abandon Zimmerman's appearance and took on the form of a German soldier. (TV: Let's Kill Hitler)