Kamelion (Gerald Flood - voice)
Kamelion was a shape-shifting android which was discovered by the Master on Xeriphas. The Master used Kamelion to impersonate King John, in a plan to prevent the Magna Carta from being signed. Controlled by telekinetic power, the Doctor gained control of Kamelion during a battle of wills with the Master.
Capable of independent thought, Kamelion asked to join the Doctor, Tegan and Turlough, and was welcomed aboard. Although Kamelion travelled with the Doctor for some time, the android rarely appeared. Kamelion eventually came under the influence of the Master again, and was destroyed by the Doctor.