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It's the same old story. You let someone have a sabbatical and instead of coming back to work with renewed commitment, they hand in their notice. I blame the critics. If they'd panned David Tennant's stage performances, perhaps he would have decided to stick to gurning his way through another season of Doctor Who.
The selection of a new Who is a cultural event that, in Britain at least, far eclipses the election of a new Pope. The choice is nearly always surprising, but usually makes sense once the actor has settled into the role.
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Who, in a million years, would have picked leather-jacketed Mancunian Christopher Ecclestone? He didn't even lose his accent. But somehow he carried it off, and as for the contemporary dress, I like to think that I was the original inspiration for this, following my little-known period as John Pertwee's assistant during the 1990s:
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(This photo was the result of one of those serendipitous moments when you happen to be in the right place at the right time. In this instance I was walking through Hammersmith on a Sunday morning, feeling slightly the worse for wear, when I passed a hotel that was staging a Doctor Who convention. I sneaked in and ended up having a photo taken with the charming John Pertwee!)
I have no idea when the successor will be announced (and frankly, I can wait), but several names have been bandied around. A strong favourite is Patterson Joseph, who appears as Johnson in Peep Show. There has never been a black Doctor before and he would be an excellent choice. Another name mentioned is Julian Rhind-Tutt, who would also fit into the role nicely.
It is also traditional for completely inappropriate actors to be suggested as possible relacements. The wild card this time is James Nesbitt, who surely lacks the necessary otherwordly qualities. A few years ago there was talk of giving the role to the estuary-accented, floppy-haired biter of homeless people's ears, Alan Davies, which would have been a disaster.
But perhaps the most controversial suggestion of all is the possibility that Doctor Who could be played by a...woman!
I actively embrace equality of the sexes in all fields, but I must draw the line at Doctor Who. He might have two hearts, but in every other respect he is a bloke. He likes gadgets, is emotionally stunted, keeps getting lost because he won't ask for directions and seems to wear the same clothes for several days at a time. I would only approve of a female Doctor if the BBC promised to cast a butch lesbian in the role.
But not Pat from Eastenders.