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.
Terry Molloy
On television, Molloy is known for becoming the third actor to play the mad scientist Davros, the creator of the Daleks, in the long-running science fiction series "Doctor Who". He appeared in the stories "Resurrection of the Daleks", "Revelation of the Daleks" and "Remembrance of the Daleks", becoming the first actor to play the role in different stories. Molloy was initially cast in the role by director Matthew Robinson, who had worked with him before and thought his talent for voices would be ideal to recreate the part first played by Michael Wisher. Molloy also appeared in the "Doctor Who" story "Attack of the Cybermen" as an undercover policeman named Russell, again cast by Robinson. In recent years, Molloy has reprised the role of Davros in the Big Finish Productions audio dramas "Davros", "The Juggernauts", "Terror Firma", "Masters of War", "The Davros Mission" and the four-part miniseries "I, Davros". He also played Davros in a 2005 stage production, "The Trial of Davros". Molloy also took over the role of Stan Harvey in the ITV soap opera "Crossroads" from Edward Clayton when Stan made a brief visit to the motel in 1987.