Frazer Hines
Hines' "Doctor Who" debut came in 1966, when he was cast to play the part of Jamie McCrimmon, the companion of the Second Doctor (played by Patrick Troughton). Originally intended as a one-off guest character, Jamie joined the regular cast and appeared in the series from 1966 to 1969. Hines reprised the role in a cameo in the 20th anniversary serial "The Five Doctors" (1983) and as a guest star in "The Two Doctors" (1985). Hines would appear in 117 episodes of "Doctor Who" in all—more than any other "companion" actor in the history of the series. The only actors appearing in more episodes are those who played the first four Doctors. Many of the episodes featuring Jamie no longer exist in the BBC's collection.
Susan Foreman
Susan Foreman is a fictional character in the British science fiction television series "Doctor Who". The granddaughter and original companion of the First Doctor, she was played by actress Carole Ann Ford from 1963 to 1964, in the show's first season and the first two stories of the second season. Ford reprised the role for the feature-length 20th anniversary episode "The Five Doctors" (1983) and the 30th anniversary charity special "Dimensions in Time" (1993).