Martin Trueman was an astrologer who lived in East Acton, London, England. He was possessed by the Ancient Lights and began to give highly accurate readings, quickly gaining in popularity and starting a show where he demonstrated his talents before a live audience. His act caught the attention of the Psychic Channel, giving him a medium to enact the Ancient Lights' master plan on a nationwide scale. He also took an interest in Sarah Jane Smith, knowing that she had traveled with The Doctor.
The power of the Ancient Lights enabled him to fire energy blasts and exert control over his clients, as well as give accurate information about the past and future.
When his plan of possesing the world and make them "join the circle and the Ancient Lights" was foiled, he said that it was his destiny and vanished in a disintergating-like fashion and was pulled from Earth and into space. His fate after that and why he was truely "chosen" remains a mystery.
