There must be something special about London. Why else would Dr Who (BBC One, Christmas Day 6pm) keep returning there? He can cross the Universe, he can travel back into the past or forward into the future, but he seems unable to extract himself from the charms of the great wen. Evidently, the Cosmos has not anything to show more fair than the sight from Westminster Bridge.
The cybermen aren't interested in the scenery. They have no aesthetic sense. Nor are they particularly design-conscious. They cover every part of themselves in metal, except their brain. Are they stupid, or what?
The year is 1851. The Doctor has arrived just in time. Not for the Great Exhibition but for Christmas dinner. First, though, he has to deal with a man who thinks that he is the Doctor. As if that isn't enough, the cybermen are planning to enslave mankind, or at least South London. The Doctor has until the turkey is cooked to help a man recover his memory and to prevent the rise of the cyberking.
Will he manage it? Of course. There is no enemy that can withstand a sonic screwdriver and David Tennant's particular brand of irreverence. Certainly not the evil Miss Hartigan, who joins with the cybermen to crush the human race. She gatecrashes the funeral of the Reverend Fairchild, wearing a dress that would make his corpse sit up and take notice. No wonder the Doctor is sorry when he kills her.
There's a female serial (cereal) killer on the loose in Wallace and Gromit: A Matter of Loaf and Death (BBC One, Christmas Day 8.30pm). Is there a pattern here? Why would Piella Bakewell want to murder Wallace? Because he is from Lancashire? Because he likes puns? Because he hasn't changed his jumper in 13 years? No, because his cakes have made her fat. And for that he must die, as have 12 bakers before him. Alas, they did not have Gromit to protect them.
Piella turns Wallace's head. They recline in a gondola, they dance the flamenco and, in a tribute to the famous scene in Ghost, they caress clay on a potter's wheel. Just to make sure we get the sexual reference, there's a shot of dough rising. "Love is a many-splendoured thing," declares Wallace, "but it doesn't half tire you out."
Unlike the Doctor, Wallace has got only the one heart. And it really belongs to Gromit. They live in a world of whimsy, improvised rockets, mechanised trousers and elaborate contraptions for getting a body out of bed, into its clothes and downstairs for breakfast. We could do with one of those in this house.
Wallace is a plasticine Heath Robinson, Gromit his health and safety expert - with a soul. Wallace's soul has been slightly corroded by Britain's money-grabbing culture. His response to the death of another baker is, "that's more business for us"; a remark that might please a politician but not Gromit, whose reproving look shames him into silence. As he spins around on a windmill, shouting, "I'm fully in control", Wallace sounds just like Gordon Brown.
Dr Robert Beckford wants to know the truth about the Nativity (The Nativity Decoded, Channel 4, Christmas Day 7.30pm). If he had the Tardis, he would be able to find out, providing it didn't keep depositing him in London. As it is, he travels to more places in two hours than the Doctor has in 40-odd years. And his conclusion? That the school nativity play is probably not an accurate picture of the birth of Christ.
Jesus' father could have been God or he could have been a Roman soldier called Pantera. Jesus probably was born in a manger, but it was a hollow cut into the stone floor of the best room in the house, not a wooden trough. And Jewish purity laws ensured that neither shepherds nor wise men would have been present at his birth.
Various church thinkers pooh-poohed such claims. We should pay attention to the Bible, not to history. Belief is a matter of faith, not fact. In which case, why point to the Scriptures as evidence of Christ's divinity? They can't have it both ways. Bob decided that the Christmas message was not about the details of Jesus' birth but his revolutionary message: do good.
Like The Secret Millionaire (Channel 4, Christmas Day 10.30pm). No one can doubt that these extremely wealthy people have helped individuals and organisations with their philanthropy. But what is the programme really saying about rich and poor and the problem of inequality? That it's all down to choice? That there's nothing fundamentally wrong with the system? It's not just the nativity that needs decoding. So does all television. Happy new year.