10. Bernard Cribbins Is... The Fourth Doctor! (1974)
Bernard Cribbins has secured his place in Doctor Who history as both a feature film companion to Peter Cushing's Doctor Who and as Donna Noble's grandfather Wilf, who brought about the end of a certain 'Best Doctor Ever' in 2010. However, as recently revealed in the live Next Doctor broadcast, he was considered as Jon Pertwee's successor when the show's leading man demanded an inflation-busting pay-rise, which was rejected by the BBC. Initially looking for a much older actor to take the role, when the search failed they threw the net wider. Cribbins was rejected after a casual mention of his army background was seen as being unsuitable (in terms of violence) for the part and further auditions turned up no-one suitable. However, destiny called when a letter from an out-of-work actor, known as Tom Baker, living in a bedsit, asked the BBC Drama Department for any roles going spare... and the rest is history.