Clive James on Parade's End, The Thick of It, Love and Marriage: a 20th Century Romance, Vikings, Masters of Money, The Bletchley Circle, Horizon and The Three Rocketeers To tell us about the Vikings (BBC Two), Neil Oliver went to the Baltic so that he could examine the artefacts of their ancestors, who dated from so long ago that one of them built a stone ship. Was he allowed to live when it refused to float? Probably he was crowned king. Neil has a twinkle in his eye. Alas, he also has a twinkle in his voice, which can make him hard on the nerves. "So," he says playfully, "just who where the Vikings?" A regional quirk, no doubt, but it combines all too well with his long hair. As he strides along the streets of Copenhagen, he has to keep pulling his hair out of his eyes. Eventually he will figure out that his hairstyle is the tonsorial equivalent of a stone ship. A less idiosyncratic presenter, thank the Lord, is Stephanie Flanders, who is in charge of a three-part series called Masters of Money (BBC Two). So far I have seen the episode about John Maynard Keynes. She spoke about him well, apart from her knack of balancing her opinions so neatly that you can't quite tell what she thinks. Keynes knew enough about economics to predict that the reparations bill for the First World War would lead Germany into a Second World War. But although he played the stock market, he did not know enough about it to predict that it would collapse in 1929. Stephanie's message, I think, was that nobody knows enough, not even a genius. But again I was gripped by a personal reaction, because there were frequent shots of the Cambridge Arts Theatre, which Keynes financed: a testament to his humanism and imagination. I have been on stage there many times, so this was another stretch of history haunted by a personal reaction. Add up all the personal reactions and you might find it a miracle that any event stays still long enough even to be described, let alone judged. The strength of The Bletchley Circle (ITV1) was that judgment was suspended on the murderer to the extent of conceding that he, too, might have been a victim of the war. Eventually, however, the Bletchley babes did him in, which was a huge relief all round. For fans of serial-killer movies like Seven, the Bletchley show had two decisive attributes. The lighting was kept so dark that the viewer could be excused for suspecting that a defective TV set might be responsible; and the killer was all the more creepy for being a silky-voiced charmer like Kevin Spacey. Crappily entitled "The Good, the Bad and the Ugly," a Horizon special about asteroids turned up on BBC Four. There was an awful lot of "could be": a useful pair of words when you have a speculation to peddle. The asteroids could be full of water. Some of them could be destined to slap into the Earth. This last bit caught my attention. I took it personally. At my age I might not be around much longer, but I'm rather keen on the idea that my granddaughter should inherit a functioning environment. Yet the man doing the voice-over doesn't seem to care how frightening he sounds when he says that quite a lot of asteroids could be ripe to smash into us. "Scientists estimate that there could be up to a million..." My own guess is that the man-made global warming scare is now running out of puff, and that even the BBC, hitherto one of its chief advocates, could be looking for alternative threats. Only the British can make a documentary about space rockets that is as boring as an American documentary about customising motorcycles. The Three Rocketeers (BBC Four) traced the long efforts of a tiny number of British engineers "to pursue a dream." The dream is to get into orbit with a one-piece vehicle. There were a few years of delay when they discovered that they had designed the vehicle back to front, but now it's just a matter of perfecting a heat-exchanger of a kind that has never been built before. The leader of the engineers says he knows how to build the heat-exchanger but he can't patent it because somebody might copy it. Could be. In the meantime, he has perfected a tremendous hairstyle: a space vehicle in itself. Coming to an end, Parade's End (BBC Two) put Christopher and Valentine up against everything except each other. Finding that Groby Great Tree had been cut down with Sylvia's connivance, Christopher walked out on her in the direction of Valentine. As they stood poised on the edge of bed, he was still calling her "Miss Wannop." About a dozen people came crashing through the door. Would the lovers ever get it on? Stoppard had worked wonders with the story, but finally it was a tease.