For those not familiar with this Modern Moral Metaphor (where have you been living?), the Doctor travels through time and space fixing problems with charm, wisdom, wit and not a little luck, whilst his trusty assistant (glamorous, feisty, intuitive and always able to improvise) occasionally saves the day through sheer common sense.
We were watching the scene in which Martha, the new side kick, is facing the choice. Go with the Doctor - confront the mysteries of the universe, have all of time at your fingertips and the world's sexiest man as your companion or ... stay at medical school and learn about spleens. Nothing to lose but peace of mind. Would you go? asked my son. Of course, without a moment's hesitation, I said. Wouldn't you?
It's different for a bloke, he said, so we asked the others. Four girls, one sofa. Two of them would go. Two of them would rather stay here and watch Friends.
I was shocked. They might as well have told me their life's ambition was to be on Big Brother. You wouldn't go with Dr Who? What's the matter with you?
Well, they said. Don't you think it's a bit, well, twisted? The whole world expecting two people in a Tardis to sort their problems out all the time? Just expecting them to turn up and be there whenever they want? Producing miracles from a box that's bigger on the inside than the outside because there's no other way of doing it?
The following day Mrs Dizzy calls me out of surgery because the world is spinning too fast and she can no longer stand up. I feel a certain glow of pride as I rush to her aid. Charming, wise, witty, glamorous, feisty, intuitive ...
In a blink of an eye I sit beside Mrs Dizzy and produce my otoscope. Helpfully she vomits on to my shoes. The thought of Dr Who sustains me.