Last Night's TV: Extermination without inspiration

Doctor Who, Sat, BBC1; Casualty, Sat, BBC1; Top Gear, Sun, BBC2

It would take a fair amount to make me watch Doctor Who these days, but the prospect of both Richard Dawkins and Paul O'Grady taking cameo roles in a script written by Russell T Davies did the trick. That must be interesting, I thought, curious as to exactly how he was going to deploy them. Could they possibly be in a scene together? Would they, in some way, interact with the Doctor himself, perhaps offering their respective expertise in evolutionary theory and cross-dressing comedy to help the save the world? It all seemed rather promising. So you'll understand that I felt a little gulled when they came and went during a bit of in-drama channel flicking, as some of the characters hunted for information about the day's big news story: the instantaneous removal of Earth from the solar system and its arrival in a planetary cluster of 26 alien worlds.

I would have thought this might have caused a bit of disruption to the schedules, but Paul O'Grady was still stalwartly doing his afternoon show, sticking in a topical joke that put the astronomical change of view down to his own excesses: "What was I drinking last night? Furniture polish?" he yelped, to the obedient laughter of a studio audience who were apparently unwilling to waste their tickets simply because the laws of time and space had been violated and left for dead. Professor Dawkins, meanwhile, was appearing on a programme called "Universally Speaking", where he was still fighting the good fight for scientific reason. Both guests did rather well, though I couldn't help but feel that they were slightly upstaged by the dummy news bulletin that had preceded them: "The United Nations have issued an edict asking the citizens of the world not to panic," read a solemn newsreader. Oh, yeah, that'll do it, I'm sure.

After that, I'm afraid I began to lose interest, since for every new planetary neighbour Earth had gained, there seemed to be an encore appearance from characters who had appeared in earlier episodes or spin-off series, all of them coming together at one point for a video conference about how they were going to get Earth back home in time for tea. There were also a lot of Daleks, of many different types and dates of production, as if they'd chosen Earth for an enthusiasts' convention, at which the bonnets would be opened up so that the various squirming octopus-like inhabitants could be inspected at leisure. And my brain began to lock under the repeated assault of the kind of lines that could be scattered at random over any Doctor Who episode at all without seeming out of place: "But... that's impossible!"; "It can't be!"; "Exterminate! Exterminate!" Change the record, guys.

I wouldn't usually watch Casualty either, though millions of people do, a number increased by one this week after I saw that the title was a Larkin quotation, "They Do Not Mean To But They Do", this being the printable bit of his famously gloomy couplet about what your mum and dad can do for you. It turned out to be a reference to a couple of separate storylines about difficult mother-child relationships knitted together (as storylines so often are in Casualty) by a crunching collision of automotive steel and human flesh. After which everyone repairs to accident and emergency to throw punches, learn home truths, hiss poisonous remarks at their colleagues and occasionally despair about the future of the National Health Service. Always worth dipping into, though, because of the writers' matchless devotion to melodramatic coincidence, which can make it one of the funniest programmes on television. Stand-out scene this week was the perfect timing of the long-lost son's heart attack, felling him just as his mother had finished screaming that she never wanted to see him again. She did not mean to, but she did.

Top Gear is back, too, equally self-parodic in its commitment to the tried-and-tested recipe. This is yet another programme that is giving me extra reading time at the weekend, but it's not hard to see why it is so popular with its target audience, which it hits with a crackshot accuracy. Jeremy Clarkson always strikes me as the sort of person who would swerve to hit a kitten, but there's no denying the brio with which he maintains his brand image.

Last week's opening episode feinted towards social responsibility with two items on fuel consumption: a supercar race that established that, flat- out, you'll only get 1.7 miles per gallon from a Ferrari, and a race between a Prius hybrid and a BMW in which it was the latter that proved to be more economical. The team's persistent implication that they are the naughty boys of the BBC is, incidentally, ridiculous. They are golden boys, in terms of foreign sales and audience figures, and probably wouldn't be expelled even if they drove a Hummer across Mark Thompson's lawn and in through his front door.