10 Doctor Who Guest Stars Who Came Back In Bigger Roles

4. Colin Baker

Colin Baker has been permanently instilled within the legacy of Doctor Who for his portrayal of the Sixth Doctor (and not necessarily for the right reasons, no thanks to that horrendous coat...) but, way back when, his only claim to fame as far as the Whoniverse was concerned was as "just another one" of its guest stars. Nobody special here, nothing to write home about... He was never really just a guest star, of course, because the fact he was later promoted to the show's leading role is enough to vouch for the fact that he left quite the lasting impression on producers during his brief stint as Gallifreyan Chancellery Guard Commander Maxil in the 1983 Fifth Doctor serial Arc of Infinity. He went from portraying one Time Lord to another (which just so happened to be the show's titular one - no biggie!) after shooting Peter Davison with a blaster gun and locking him in a cell. You could say that this was Colin's way of trying to write off his predecessor before his time (Baker wouldn't actually take over the role for another year and a bit) but that's how rumours start and lives get ruined. Colin Baker isn't the only Doctor Who actor to go from guest role to star of the show, but let's not get ahead of ourselves. Onwards!