With the news that Matt Smith is to leave the role of The Doctor (let's call him Eleven from here on in) at the end of the show's current 50th year, Doctor Who's producers have a crucial decision to make in appointing the right actor - or actress - to take on the role of Twelve.
I've been a lifelong fan of Doctor Who, although in my case I was still only four years old when Sylvester McCoy became Seven, so don't really have clear memories of any of the Doctors who came before him.
Before I list some of the options, let's remind ourselves of the Doctors of the past:
1. William Hartnell (1963-1966), 2yrs 11mths
2. Patrick Troughton (1966-1969), 2yrs 8mths
3. Jon Pertwee (1970-1974), 4yrs 5mths
4. Tom Baker (1974-1981), 6yrs 9mths
5. Peter Davison (1981-1984), 3yrs 0mths
6. Colin Baker (1984-1986), 2yrs 9mths
7. Sylvester McCoy (1987-1989), 2yrs 3mths
8. Paul McGann (May 27th 1996), 1 day
9. Christopher Eccleston (2005), 3mths
10. David Tennant (2005-2010), 4yrs 7mths
11. Matt Smith (2010-2013), 3yrs 11mths
Although it might feel like the actor playing The Doctor has changed quite a lot since the show's return in 2005, that's actually not the case - with the exception of Eccleston's admittedly short tenure, Tennant and Smith have been two of only four actors to play the part for more than three years (with Davison piloting the TARDIS for almost exactly three years, but falling just a few days short of the milestone).
