I owe Sam Neill an apology. A big, big, big apology. Last week, I thought he was acting; apparently, he was already dead. Silly me. I couldn’t tell the difference. In mitigation, the DVD of the first episode of The Tudors I was sent had a long opening sequence that I thought was a tease of things to come. One of which was Sam. These are often included in critics’ preview packs. In fact, as the sharper of you will have noticed, they were scenes culled from the first series, at the end of which Neill died. Then my disc had the whole first episode, including the naughty pastry chef getting boiled alive. “Head first or as it comes?” he was wittily asked by his dunker. Anyway, sorry, Mr Neill. You do, though, have the singular privilege of having suffered a stinker of a review without ever having got out of bed. I owe you one.

Next year is the 200th anniversary of the birth of Charles Darwin. For a person who was never a member of the Groucho Club and never owned a production company, Darwin has been responsible for an enormous amount of television: nature programmes, police and medical dramas, reality shows. It will also be the 150th anniversary of his reluctant publication of The Origin of Species, a book that not only changed the world, but also explained it. Television likes an anniversary, and this is a particularly auspicious one, for our greatest scientist and arguably Britain’s pre- eminent original thinker. Unlike the ideas of Newton or Hobbes or Adam Smith, natural selection is clearly understandable and explainable. And the path that led to The Origin of Species is properly exciting. In fact, it is probably one of the few significant scientific discoveries of the past two centuries that is accessible to everyone, as well as affecting everyone.

So, Darwin deserves a landmark, flog-it-round-the-world showcase series. And, just as obviously, the natural selection for a presenter should be David Attenborough. In survival of the fittest, there is no second best: there are just winners and lunch. Richard Dawkins is lunch. In fairness, Darwin is his thing, his fundamental belief; he has been a devoted acolyte of the great bearded ape all his life. His day job is Oxford professor of science PR, so being asked to make the defining series on his hero was a big opportunity that he grasped with both hands — then dropped. Maybe it was nerves, perhaps he’s just too emotionally involved, but the first episode of The Genius of Charles Darwin (Monday, C4) left Dawkins blinking in the headlights.

It also revealed a sorry truth. He is much happier, and much more accomplished at, knocking things down than building them. He’d rather be against something than for it. Confronting a class of quiet, respectful, eager and religious schoolchildren, he became tongue-tied and muddled about selling evolution. He was much happier attacking religion. His anger and bombast stand in stark contrast to Darwin’s quiet, inquisitive humility. Darwin was a gentle man who thought deeply and went out of his way to avoid confrontation or to incommode others. Tellingly, he managed to live his entire life with a devout Christian.

This was a great opportunity for a lush, life-affirming, invigorating series, but what we got was a confused liturgical spat. Much of the blame must fall to the producer, who really should have made sure there was a far more rigorous and inspiring script. In the end, the wisest and most memorable observation came from the mouth of a schoolboy. After a day on the Jurassic coast, discovering ammonites, he said that yes, he believed in evolution, then paused and, with a faint smile, added: “But I’ll still say my prayers.”

A lot of people ... well, some people ... okay, two people called to make sure I’d seen A WI Lady’s Guide to Brothels (Sunday, C4), and indeed I did. There was little else to watch last week. But I really wasn’t as keen on it as they all — well, both — seemed to be. It was a fine example of a condition that is becoming the curse of factual television: galloping formatitis with secondary scenarioism. Programmes catch this from being left out too long, then over-sold and overanalysed by people who are fearful of making mistakes.

A production company will go to a commissioning editor and say: “We want to make a documentary about ordinary women’s attitudes and concerns towards prostitutes and prostitution, based on the WI passing a motion saying prostitutes should be protected.” And instead of going “Fine, here’s the money, show us a rough cut when you’ve made it”, the commissioning editor says: “I like that, but how exactly are you going to do it, and precisely what are you going to show? And what conclusions will you come to? And how are you going to get empathy and excitement?” Instead of trusting a story to tell itself, or employing people you trust to tell it, editors demand to know exactly what they’re going to see before it happens. It’s like demanding to know the winner of a horse race before you’ll allow it to start. The straitjacket of format dictates every shot and reaction. The film becomes a gymkhana, jumping prearranged fences against the clock, and the pitch is the story.

So, they got two straight-up ladies with buns and glasses, then took them to sex shops, where they were asked to examine butt plugs, and to brothels, where they took an interest in the plumbing. Then on to the girly ranches of Nevada, which I think must exist solely for the benefit of documentary crews. Here they had an utterly predictable chummy meeting with working girls, as if they were some Amazonian tribe. Then, back home, a journalist tried to set up a mobile brothel, which became a segment from What Caravan?. All this was stitched together with unconvincing links and telephone calls.

Somewhere in all this restrictive belt-and-braces formatting was a rather good programme, perhaps even an important one. But it never got to go anywhere interesting or illuminating because there was no time to pause or be discursive, there were so many boxes to tick. Factual television is becoming repetitive and predictable through fear of getting something that won’t fit into a strand or to a time or a demographic. All this second-guessing is ultimately censoring the inquisitive camera.

Unhitched (Thursday, FX) is a new comedy about four of those improbable American sitcom characters living together in an even more improbable sitcom house and cavorting through classically hilarious sitcom scenarios based on dating. Dating is a weird ritual practised only by Americans and possibly invented as a leitmotif for sitcoms. We all know about it because we’ve watched so much American TV.

Everyone else in the world has work and social lives, out of which emerge partners and spouses and mistresses; but Americans have work, social lives and this dating thing. In the first episode, someone fell in love with a prostitute, someone else went out with a man who turned out to be the leprechaun mascot of a basketball team and someone was anally raped by an orang-utan. There’s also a comedy Indian, as in subcontinent, of a rare racial stereotyping I haven’t seen on television since Mind Your Language. If you’ve been waiting for the next Frasier or Friends, dream on.

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