"The Critic". Pilch

Among the Big Three of Richard Brinsley Sheridan's comedies from the 1770s, 'The Critic' (1779) is the hardest for modern audiences to get their heads around. It's so full of direct, contemporary, satirical references, and personal attacks on real people who were famous then but are now long forgotten, that an awful lot of the script, if performed straight, must perforce go right over most people's heads. In the same way, comedy sketches on 'That Was The Week That Was' from 1960 about the Profumo scandal still make my 94-year-old dad chuckle, but most people under 30 would grasp only the barest hint of the wit - even though the language itself is still within living memory.

'The Rivals' (1775) has none of these barriers. Its characters are archetypes, eternally recognisable and inflated to hilarious proportions by Sheridan's puns, plots and provincial poshness. 'The School for Scandal' (1777) is more anchored to a specific and sordid London society, but even there the story of marital misunderstandings has stood the test of time. It's like Ayckbourn with cuffs and wigs.

Unlike these earlier plays, 'The Critic' doesn't even have a plot as such. It has two main scenes: first the critics make fun of playwrights who come to visit them; then they attend a rehearsal and make fun of it. That's it. Apart from picking up the contemporary references, the laughter arises from recognising the theatrical tropes that are being lampooned. And to be fair, a few of these, such as fake kissing, are still relevant. But the majority mean next to nothing at a distance of 250 years.

So what is a modern production of 'The Critic' to do? Director Phoenix Barnett of Playing Productions has come up with a genre-busting idea that aims to supercharge his production at The Pilch this week. He has made the entire show a play within a play - or, to be more precise, a rehearsal within a rehearsal. The 'director' (Wendy Shi) is watching throughout, and frequently leaps up asking the actors to make adjustments. In one early intervention she asks Mr Dangle (Gillies Macdonald) to be 'more preening', a note he takes over-literally and spends the rest of the scene compulsively stroking his own body.

The director's interpolations are of course in modern English, and are accompanied by plenty of annoyed swearing, particularly from Hugh Linklater's Sneer, who can't wait for the rehearsal to be over.

These sections are funny, but they also give the audience a route in to the rest of the show. The director is, in effect, watching and commenting on 'The Critic', even as the Critic is watching, and commenting on, Mr Puff's masterpiece 'The Spanish Armada'. Clever.

But there are also pitfalls with Barnett's brainwave.

One problem is that the 'modern' sections may provide an easy entry point to the play, but they do nothing whatsoever to make the 'original' sections any more explicable or accessible. They are an extra layer on top of Sheridan but, like oil on water, they don't penetrate or change the element below.

To compound this, the way that the company approaches the original lines betrays a certain lack of empathy with Sheridan as a writer. They aren't just larger-than-life, they're somehow different-from-life. Noam Sala Budgen as Mr Puff, for example, gives a truly impressive performance of astonishing energy, farcical focus and pink-faced outrage, but at the same time his delivery is so exaggerated that it seems to miss the true heart of Sheridan's humour. It's a slight tonal misfire that is replicated across the production.

The other problem with the 'modern director' concept is that, despite being a great idea, it's also here something of a missed opportunity. In this production, the director keeps interjecting in the same way from start to finish. But she could have also offered a way to introduce a real - and even funnier - element of narrative development to the show. In other words, instead of going round in circles, the idea could have built to some sort of resolution, adding genuine plot value.

Even with these caveats, there is plenty to enjoy in this 'Critic'. The set and costumes are delightful (with particularly impressive attention to detail on the contemporary newspapers). Mr Fretful (Cameron Maiklem) has some perfectly timed asides, and his forced laughter (half hilarity and half the agonised scream of a man being tortured) is infectiously painful. The satire of tedious on-stage exposition between Sir Christopher and Walter Raleigh is every bit as relevant today as it was in 1779. And the blatant piece of Shakespeare plagiarism is explained away with an insouciant simplicity that makes you yearn for more of the same ('That's of no consequence. All that can be said is, that two people happened to hit on the same thought, and Shakespeare made use of it first, that's all').

Playing Productions have approached this classic with enthusiasm, wit and imagination. Unfortunately, 'The Critic' is just an incredibly hard nut to crack. My advice: next time, do 'The Rivals'.