The thing about zombies is they make us feel better.

We think to ourselves: the economy is wrecked and the Tories are still in power, but at least there are no shuffling reanimated cadavers out there who want to eat our brains, so it could be worse. I can think of no other explanation for the rise and ubiquity of zombies on British television. Before long, not only will zombies be appearing in programmes, they will be presenting them as well (frankly, in some cases they already are).

The latest example of this trend is In The Flesh (Sunday, BBC Three, 10pm), a three-part drama that highlights one of the problems with the zombie genre, which is that zombies are right on the line between serious and silly. One minute you're watching the living dead; the next, all you can see are hundreds of hammy extras doing bad shuffle-walks in their desperation for an Equity card. Suddenly, it's not horrific. It's hilarious.

Sadly, that is exactly what happened to the opening scene of In The Flesh. Our first glimpse of a zombie was supposed to be scary but the zombie was wearing a party frock and looked like a reanimated Violet Elizabeth Bott. It was also gargling like it was in an advert for zombie mouthwash (which they would definitely need because eating brain is bad for your breath). The aim was for shocking; the result was silly.

It was a problem that dogged the whole of the first episode, and it's the same in tomorrow night's episode: the tone is not quite right. Is this drama? Is this comedy? If you're going to do a zombie drama, you have to take it 100% seriously, otherwise the audience will spot the inherent silliness of the idea and start giggling. The makers of In The Flesh clearly do not understand this so try to get laughs, with fairly disastrous results for the believability of the whole project.

I can see why they tried to do it this way because the basic premise – that zombies can be treated and reintegrated into society – has some good satirical potential. It means the zombies can represent pretty much any enemy within that gets you going: immigrants, teenagers, criminals, whatever. The idea that zombies can be rehabilitated also allows for some nice satire of the fearful, wishy-washy way certain institutions treat criminals. The zombies aren't killers, they're misunderstood; they aren't evil, they're merely victims of PDS or Partially Deceased Syndrome.

This does at least put an original twist on the zombie idea, but don't we deserve an entirely original drama rather than an original twist on an old and tired one?

In The Flesh is a timid idea pretending to be a brave one – timid because, behind all the slavering and brain-chomping, this programme has only strayed a few steps away from a tried and tested format. There will come a time when we are tired of the zombie drama. I think I can sense it happening already – it is in a kind of living death. The zombie drama is doomed.