There is something woefully amiss in modern television comedy. It should not take me to point this out, given that, like many women I know, I have not laughed out loud at on-screen light entertainment since an episode of Crackerjack around 1981. But here goes: this something being missed is crucial to a comedy’s appeal, and even the most lauded comedians are still missing it. It’s called likeability.

As a teenager I was told you had to like your driving instructor to pass your test. That ended up proving so true, I extended the theory to hold that you have to like your doctor to really be cured, and, even more true, you have to really like your doctor if you’re going to have an inappropriate affair with him. Most obvious of all, you have to like the central character if a television comedy is to work.

That is why, although both brilliantly written, Flight of the Conchords triumphs over Peep Show. The first features a likeable pair of New Zealanders, the second features a pair who you would struggle with in a game of “Do, Dump or Marry”.

This is why Seinfeld wins over its spin-off, Curb Your Enthusiasm – at least Jerry Seinfeld made sure he was the best of a loathsome bunch, rather than the worst. Ricky Gervais knew this simple truth when he made Tim the heart and soul of The Office rather than his monstrous David Brent. If you don’t care what happens to your characters, you’ll never be bothered to tune in next week.

And this is why, although I sort of hate myself for writing this, a garish show about estate agents wins over the far greater talents of Jack Dee. Sold, the new comedy that began on ITV last night, is based on one preposterous joke: that an estate agent can be nice. Funny, huh? And not just nice – the Danny character (Bryan Dick) stretches credibility beyond any estate agent’s particulars – he is nothing short of a latterday saint of For Sale boards. He sees his job as part social work, part marriage guidance, partly to give his own home away to a needy single mother of a disabled boy. His mission is to save the world, one exchanged contract at a time.

This paragon is squared up against the devil incarnate, an estate agency manager named Matt (Kris Marshall). By contrast, of course, the realism of the evil estate agent seems almost documentary. In fact, chunks of the plot about this firm of estate agents called Colubrine appeared to have been lifted intact from a BBC undercover news investigation of estate agents for the Whistleblower series last year.

Some of Sold’s flaws could be explained away as appropriate to its subject matter. The setting is oddly stuck in the 1980s, all flash cars and shoulder pads – as is, I suppose, the property world. And the killer putdowns given to Matt are disappointingly sub-Simon Cowell, on one house, for example, he comments: “What are you, the Taleban – this is an atrocity.” This again, is probably accurate about the kind of witty repartee you can expect from your “sales negotiator”, although less than entertaining (if we wanted to spend more time with real estate agents . . . well, no one would).

What is thrilling though, is watching Marshall, best-known as the drippy boyfriend in the BT adverts, playing someone so wicked. He’s shockingly good. And that is where the allure of this ridiculous, unbelievable, camp series lies – in the battle of good and evil you are rooting for both. You know each have to become more like each other – and that’s worth watching.

Lead Balloon also began a new series last night on BBC Two, featuring Jack Dee playing a comedian even more odious than his normal persona. (Incidentally – Dee looks like he’s aged about half a century. It must be frown lines.) The show is obviously derivative of Curb Your Enthusiasm, and they share the same problem. When the most endearing character is Dee’s aggressively miserable cleaner called Magda, you’re in trouble.

I know the joke here: that the star humiliates himself on screen by making himself almost unbearably unpleasant. It’s a self-deprecating inversion of the usual star vehicle. Nice try. But a friendly word in your ear Jack: “likeability”. That’s all I’m going to say.

Out of the box

–– My grandmother was once sent a brochure for occupational health products that helped people to live independently for longer. At the age of 92, and still living in her own home, she was their ideal target market. But so, I discovered with some shock and then delight, was I. Flicking through it I realised they had a whole untapped customer base: those that have no physical trouble living independently, but are spiritually extremely lazy. One product I particularly recommend to readers of these pages are the “bed spectacles”, or “television glasses”. They allow the viewer to watch their favourite shows while lying completely flat in bed. You may not have thought you wanted it, but I bet, secretly, you do now. And there’s still time for Christmas orders.

–– Is anyone else watching vintage 1960s Batmanon BBC Four? And am I alone in thinking how refreshing it is to see an unaerobicised beer belly on a superhero?

helen.rumbelow@thetimes.co.uk

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