Vogler

 was a German weapons smuggler. Policeman Sung-Chi Li was investigating him in 1937 Shanghai. Li found out about an arms deal that Vogler was going to make. The deal, which was with Kwok and Hsien-Ko, was interrupted by the Fourth Doctor and Romana I. This made Li move in to arrest them prematurely. In the confusion, Kwok and Hsien-Ko killed Vogler so he would not reveal their identities, then escaped. (PROSE: The Shadow of Weng-Chiang)