There’s something wrong with Oedipus. Unfortunately, thanks to the wilful misdiagnosis of Herr Doktor Freud, the cat’s out of the bag. In our post-post-post-modern era you can’t open so much as a set of lawnmower instructions without being blindsided by analysis of boys and their mums (I’ve always felt Jocasta gets off rather lightly in the ‘Oedipal’ philosophy . . . but no matter.) While this may seem like handy theatrical publicity, though, the very mention of Oedipus now presages so much that, no matter how adroitly a production works the Theban tragedy, there is a major problem in terms of building narrative intensity. In short, everyone knows what’s coming.

Jonathan Kent and his team have not surmounted this problem. There is no shock here; no horror to the revelations; no – oh, what’s it called? – drama.

As Oedipus, Ralph ‘Raif’ Fiennes is underwhelming. Shaven-headed and short-sleeved, he is more bank manager than king. His voice is barrow-boy rather than bass-baritone, so his arguments with Creon (Jasper Britton) end up closer to a squabble between Phil and Grant Mitchell (leaving Claire Higgins’s Jocasta as, what, Pat Butcher?).

Teiresias (Alan Howard) comes dressed as an art-history professor, his squawking voice half Emperor Palpatine, half Under Milk Wood. And the chorus look (and sing and dance) less like Greek elders than drunk barristers.

Nothing is improved by Frank McGuinness’s unmemorable re-write. It veers between “You intend to do the dirty?” colloquial and we-beseech-the-gods speechifying; the Thebans pray inconsistently to ‘gods’, ‘the god’ (Apollo, presumably) or ‘God’; and it is ridden with glib one-liners, poached turns of phrase and faintly distasteful attempts at humour.

If the intention is to demonstrate that ancient themes are time-proof, it doesn’t work: you can’t have people taking the Delphic oracle at face value in modern English.

As Oedipus did everything possible to escape his undeserved fate (moral: you can’t, so don’t bother), I wondered which bright spark decided that this was a parable for our times. Not even religious folk believe in Fate now. Meanwhile, the big question – why that maternal taboo is so universally dominant – the one which has filled theatres for centuries, is no closer to being answered.

To judge from the coughing and throat-clearing, the audience were largely unmoved. The eye-gouging got a reaction, of course, and the realisation that Oedipus’s children would carry the tragic stigma (though putting bloody hands on kids is a bit easy, isn’t it, chaps?). But the revelation that Oedipus had sired children out of his own mother? Nothing, except from a bunch of schoolkids who had the grace to say “eueeurgh” – and were promptly told to be quiet.

Hmm. Somebody fetch the Doktor.

National Theatre. Until Jan 4 Tickets: £10-£41, 0207 452 3000 (