9. Boris Karloff
Boris Karloff, the legendary actor to play Frankenstein’s creation, was no stranger to being a part of monstrous stories, almost becoming the face of the horror movie genre in the 1930s.
During the late 1960s, Karloff was in mind to play the Doctor for a spin-off radio series. He declined as he was unavailable at the time. Peter Cushing stepped in to record a pilot, but the BBC passed on the series (the original recording hasn’t been found since).
However, a clip of Frankenstein (1931) appeared in the Doctor Who movie, meaning Boris did eventually feature within the franchise, even if it was brief and not as the Doctor.