An official with the World Ecology Bureau based in London. He was party to the discovery at the South Pole of a strange plant pod. Dunbar's boss, Sir Colin Thackerey called in UNIT, and they sent their scientific adviser and his companion Sarah Jane Smith to the Bureau. The Doctor agreed to travel to Antarctica to investigate the find. Unhappy at his status in the Bureau and in need of money, Dunbar decided to sell information about the pod to the plant-obsessed millionaire Harrison Chase. He sent two men to the Pole to steal it, a scientist named Keeler and his henchman, Scorby. Dunbar was horrified to learn that the scientific base had been destroyed, and its occupants killed. He later tried to make amends by going into Chase's mansion alone to confront him. However, Keeler had become infected by a second pod and had mutated into a Krynoid. The creature attacked and killed Dunbar.
Played by: Kenneth Gilbert. Appearances: The Seeds of Doom (1976).
- Gilbert fell ill during the making of the story, necessitating director Douglas Camfield to heavily rearrange his studio days to hold Dunbar's scenes back for after he had recuperated.