Imagine writing this: “It is my belief we are standing on the very edge of history.” Having written it, what would a normal, sensitive, moderately intelligent person do? Well, 99% of us wouldpush the delete button with a faint shiver or tear up the piece of paper so that the young and impressionable couldn’t read it. We understand that it’s utter bilge, but, you see, that’s why we’re not scriptwriters. It takes a very special person to write that sentence and think: “Yes, high five, nice job, really profound! What shall I do next?”

How about adding onto that sentence: “A watershed”? Takes your breath away, doesn’t it? You see, only a top-notch scriptwriter could make that leap into the literary darkness and come up with not just an edge to history but a watershed to go with it, like a garden feature. The scriptwriter then gave that line to a director who, like him, has a very special skill: he hears words only for their timbre and rhythm and how much time they fill up. The director handed them on to an actress, and she popped them into her mouth, because that’s what actresses do when they’re told to, then she let them out again in front of a lot of other actors and a camera, and finally it was broadcast into your living room, where, through no fault of yours, it stuck in your head, where it’s damn hard to get out.

This gem of the scriptwriter’s craft was brought to us courtesy of Burn Up (Wednesday/Friday, BBC2), the hugely expensive and very Canadian and cavernously vacuous thriller about Kyoto and global warming that starred Adam from Spooks and Josh from The West Wing. Watching it was a bit like being manacled to the table at a Notting Hill dinner party, or being lectured by a vegan vitamin salesman.

The finger-wagging about global warming was relentless and unabating, all couched in the comfy velour of the edge-of-history and watershed gibberish. The goodies were witty, brilliant, sensitive, imaginative, attractive, sexy and great dancers - rather, I suspect, like the scriptwriters. The baddies were, well,they were all American. This was film-making from the Soviet school of political subtlety, a childishly black-and-white premise, delivered with a patronising blog of a script, which overwhelmed the plot, pace, anything resembling a character and, finally, the audience’s sympathy. Last week, George Monbiot, The Guardian’s geography teacher, wrote that Channel 4 had done more environmental damage than any other organisation by showing its devil’s-advocate documentary, The Great Global Warming Swindle. This was obviously before he’d seen this bloated, wasteful, gaseously hypocritical beached whale of a miniseries. Because it is this sort of toadying and special pleading that will poison the good intentions of the green movement. It’s not the arguments or the facts or the science that are in doubt, it’s the people doing the arguing. There is nothing like enough politically and socially committed fiction on television, but this dim, deaf drama was an object lesson in how not to make it; and the real inconvenient truth for the green movement is, as the old Jewish retail expression has it, in winning the argument they’ve lost the sale. They suffer the fatal flaw of being too smug to bear. There is a global resistance, not to the facts, but to environmentalists. It appears most of us would rather fry, drown or starve than be told what to do by a bearded git in sandals, and that’s a rather comforting and cussedly human truth.

The Wire (Monday, FX) started its fifth and final series last week. I do understand that it’s a widely accepted convention that reviewers watch programmes before criticising them. Nevertheless... The Wire is masterful, gritty, smart and gripping television, and you really should see it. But I won’t, because I’m still three series behind, thanks to all the other telly dross I have to watch in-between. In fact, I’ve just bought the box sets of the first four seasons in New York, and the man in the HBO shop who took my credit card said, with a hushed reverence: “These are the very best programmes to be shown on television ever, but you can’t just watch them, man. You need to look at them like Dickens. With respect.” I know what he meant, and it’s a golden compliment, but coming from the land cursed with costume drama, and having grown up with improving classics every Sunday, the best thing I can tell you about The Wire is that it’s definitely, categorically not costume drama.

Travellers’ Century (Thursday, BBC4) is a neat idea for moving television travel on from gap-year adventures. Benedict Allen began by explaining that the 16th and 17th centuries had all been about discovery, the 19th about exploration and the 20th about travellers, for whom the trip itself was the point, the destination merely a moveable excuse and something to sell to the publisher. It’s a nice conceit. He chose three very English knapsack-and-pipe voyagers: Eric Newby, Laurie Lee and Patrick Leigh Fermor. All were writers, and all were travelling to get away from home rather than to get to anywhere in particular. The 20th was also the century of escapism.

They are, it must be said, a prep-school teacher’s safe trio. As I Walked out One Midsummer Morning, Lee’s travel book, is not a patch on Cider with Rosie, his staying-at-home book; and Leigh Fermor is insufferably patrician, verbose and snobbish. Newby is easily the best of the bunch and was the subject of the first programme, which turned out to be strangely flat, considering it was about mountains, and pedestrian, a fatal flaw for a travel programme. It didn’t seem to go anywhere much. Old codgers said nice things about the author, Allen retraced his steps to Afghanistan, but it might have been Snowdonia with hats. It was all rather a shame, though it pointed out a truth about travelling as opposed to discovery or exploration: that journeys are only ever as interesting as the traveller. A dull storyteller can make anywhere prosaic, and sadly, for all his public-school enthusiasm, Allen was loquaciously plodding when it came to making a short walk into a saga. His ability to describe what was in front of him was smothered by the writing of Newby and the Hindu Kush.

John Barrowman’s The Making of Me (Thursday, BBC1) was a strange little unreality doc that set out to discover whether you are born or made Scottish. Barrowman was conceived north of the border, but to all intents and purposes has grown up to be theatrical. We followed him back to his parents’ house to discover if there was a Scottish gene, or if Scottishness is imparted through playing with dolls in skirts and eating fried mince. Astonishingly, the moment Barrowman saw his mother, he began speaking in a broad Aberdonian accent, proving what most of us have guessed: being Scottish is down to having a powerful and overbearing mother. There was some other stuff about whether or not he was born gay, but this was less interesting. Who cares? Nobody ever asks Andrew Lloyd Webber if it was nature, nurture or necessity that made him straight. The existence or not of a gay gene is just too close to pink eugenics, the creation of two-tier homos, real and lifestyle gays. It’s what you choose to be on Saturday nights that counts.

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