Heldorf
Professor Heldorf was a scientist who came to the United Kingdom as a refugee, after which he retained traces of his original accent. (PROSE: The Ambassadors of Death) He was forced to work for General George Carrington, examining the ambassadors.
When General Carrington ordered Professor Heldorf to increase the radiation that they were giving the ambassadors, he instead insisted that they needed antibiotics, blood transfusions and cortisone injections. However, the general threatened him into doing so. The professor later realised that Reegan meant to have him and his assistant killed and flung himself at his henchmen, but he was shot and killed in the attempt. (TV: The Ambassadors of Death)