Harry Sullivan (Doctor Who)
The character was originally devised by the production team to do any action scenes required in episodes when they had envisioned that the new Doctor would be played by an older actor (Sarah-Jane even jokingly compares Harry to James Bond at one point). When forty year-old Tom Baker was cast, however, this was no longer a concern and the decision was taken to write Harry out — something producer Philip Hinchcliffe later admitted was probably a mistake, as Harry was a likeable and popular character who worked well with both of his fellow leads.