Judging by the trailers, Bonekickers, the BBC’s new Tuesday night drama, promised a piece of enjoyable hokum – a West Country Indiana Jones meets the Da Vinci Code – offering a perfect and undemanding way to wile away the summer evenings. 

But that’s not how it turned out at all.

The plots are utterly preposterous, the dialogue clunky, the jokes leaden and the acting laughably wooden – but that isn’t really the problem.

We would put up with all these faults if the show offered in compensation a bit of uncomplicated fun – after all we lap up American series from Buffy the Vampire Slayer to Heroes to Desperate Housewives with uncritical relish.

No, the real problem is that the political commissars of the BBC no longer produce anything as straightforwardly simple as light entertainment.

Everything, from children’s programmes to prime-time drama, has to be saddled with a leaden, lumbering, clunking political message.

It has happened before in shows including Spooks and Robin Hood, and now it’s poor Bonekickers’ turn.  

What should be a joyful romp has been transformed into a crass piece of indigestible left-wing agitprop.

It illustrates perfectly the liberal intelligentsia’s true view of the lumpen proletariat – the plebs can’t be relied on to read the Guardian, so they feel they must insert subliminal messages into popular drama instead.

The first episode for example featured a group of bloodthirsty Christian terrorists who were persecuting peaceable Muslims (any Muslim portrayed in a BBC drama is invariably impossibly saintly).

Just in case you failed to get the message – Christians are evil, Muslims are wonderful – you were constantly hit over the head with it for the next 60 minutes.

At one point a Christian thug who styled himself on the Knights Templar, beheaded a peaceable, saintly Muslim with a Crusader sword – I kid you not.

This week’s episode apparently featured evil white West Country racists and heroic black slaves, and included a US senator destined to become America’s first black president. Subtle or what?

I say apparently, because I didn’t actually watch the second episode. When I settle down to an evening’s entertainment I don’t want to be preached at by some ex-public schoolboy who thinks he’s the new Bertolt Brecht.

And it would seem I’m not alone. Bonekickers, the flagship of the BBC’s summer schedule, has seen a catastrophic decline in its audience figures. Fully 20% of viewers – 1.6 million people – abandoned the show between its first and second episodes.

Future episodes apparently will include further lectures on the evils of the Iraq war and no doubt storylines decrying homophobia, global warming, GM crops and every other fashionable cause – but by that time they’ll be lucky if two pensioners and a dog are still tuning in.

It’s about time the BBC stopped producing popular drama – especially when the shows turn out to be not so popular after all.

Let’s face it, the Americans do this thing so much better – and they don’t need £4 billion a year in subsidy from the taxpayer.