A Time Lord from the planet Gallifrey who is at least 900 years old and can take different human-seeming forms, regenerating from one to another when the need arises. While he usually uses male he/him pronouns, if in a female form he will use female she/her pronouns. Personality wise, the Doctor is an adventurous scientist who never gives in, and never gives up, however overwhelming the odds against him. The Doctor believes in good and fights evil. Though often caught up in violent situations, he is a man of peace. He is never cruel or cowardly. His physical appearance varies depending upon a number which may be specified by the writer, as follows: 1, 2, 3 or 12 = an elderly man with greying or white hair, a grandfather figure to his companions 4, 6, 7, 9 or 14 = a middle-aged man with an eccentric appearance, an uncle or mentor figure to his companions 5, 8, 10, 11 or 15 = a younger man, a dashing, romantic figure 13 = a younger woman with blonde hair, an older sister figure to her companions If no number is specified by the writer and context does not suggest an appropriate appearance, use 11 as the default