Rupert Von Thal (pronounced Von Tal) was a Victorian fraud. He pretended to be a great adventurer and world traveller in order to be able to give exciting travel lectures to members of high society, but really he was little more than an assistant to Professor Quandry.
When at last the Fifth Doctor took him on an adventure to Earth's prehistoric past, he found within himself reserves of genuine courage he had previously not known. Not only did he adequately protect Beatrice Mapp and Nyssa from scorpions, but he also gave his life to see that they would be returned to Mapp's Bloomsbury residence. Just prior to his death, he had even plucked up the nerve to ask Mapp to marry him, and she had accepted. (AUDIO: The Boy That Time Forgot)