The Doctor has had to vanquish many foes - but one of his greatest victories has been to change the mind of the man who took the programme off our screens in 1987.

Michael Grade, who at that time was Controller of BBC One, admitted he'd cancelled Doctor Who as he thought it was awful, outdated and violent with limited audience appeal.

The revived series was already in production at BBC Wales at the time of his return to the BBC as Chairman in summer 2004.

But after seeing the show, Grade revealed in an email to Director-General Mark Thompson that he'd been won over:

"This is not easy to write - as you will readily understand. But here goes - congratulations to all involved in Dr Who: to whoever commissioned it, those who executed it, the writers, the cast, the publicity folk that promoted it, the schedulers and of course the late Sydney Newman who invented the whole thing.

"I truly enjoyed it and watched it every week with my six and half year old son who is now a fan.

"A classy, popular triumph for people of all ages and all backgrounds - real value for money for our licence fee payers.

"PS never dreamed I would ever write this. I must be going soft!"

Grade also took the opportunity to step inside the Tardis on a visit to BBC Wales headquarters in Cardiff in June 2005.

Whether he underwent a mind-warping operation while inside remains unknown - but now that he's left the BBC again to run ITV Grade will need all his wits about him as he tries to battle the Doctor's popularity on Saturday nights.