The Third Doctor is an incarnation of the Doctor, the protagonist of the BBC science fiction television series Doctor Who. He was portrayed by actor Jon Pertwee. Within the series' narrative, the Doctor is a centuries-old alien Time Lord from the planet Gallifrey who travels in time and space in the TARDIS, frequently with companions. At the end of life, the Doctor regenerates. Consequently, both the physical appearance and personality of the Doctor changes
Add actors/actresses and cast the roles/films/series that they were rumored, considered, offered, negotiated, auditioned, turned down, and/or originally casted before getting recasted. (Please double-check in research.)