Melissa Blease reviews Pygmalion on at Theatre Royal Bath until Saturday 8 April

One of your friends has just let it slip that a casual acquaintance recently referred to you as being “a bit posh”. Do you defend yourself? (“Me, posh? Hardly!”). Are you insulted by the accusation (“Me, posh? That’s ridiculous!”)? Or are you actually a little bit smug (“Me, posh? Oh, teeheehee!”)? Whatever your reaction, you have to admit that being called “a bit posh” is surely better than being referred to as being “a big common”. Because, whether you like what I’m about to say or not, we’re defined by a very British, intricate but not always subtle set of social rules that dictate the way we speak, dress and behave (do you call your evening meal dinner, tea or supper? Do you shop at Waitrose or Asda? Are your friends barristers or baristas?), and which reflect the ‘kind of person’ each of us sees themselves as.

When George Bernard Shaw’s Pygmalion first debuted 100 years ago, and put issues such as the poverty gap, gender inequality and perceptions of what constitutes a ‘good education’ in the spotlight, it was seen as a groundbreaking work that forced a whole class of British people (namely, the middle-to-upper-classes, of course; the working classes were too busy drinking gin at the nearest Music Hall) to reconsider which social tribe they most closely identified with – well, for one evening, at least. But while the prospect of Professor of Phonetics Henry Higgins taking on the challenge of turning Eliza Doolittle, a girl who sells posies for a penny a bunch on Drury Lane, into into a debutante worthy of a meet’n’greet with the King was a fascinating notion, little about our stuffy old principles changed; whether you said ‘laff’ or ‘larf’ still meant the difference between a smooth climb up the social ladder or a rapid slide back to the gutter. A century on, and the Great British Social Divide still offers little to laugh about.

In this thoroughly refreshing revival of Shaw’s most popular play – a co-production between the innovative Headlong theatre company, Southampton’s Nuffield and the West Yorkshire Playhouse – director Sam Pritchard has put a totally modern spin on proceedings, taking the audience right out of their comfort zone of familiarity (even if you’ve never seen Pygmalion on the stage you’re surely acquainted with the cosy, saccharine-sweet 1964 musical film adaptation My Fair Lady, in which Audrey Hepburn makes even moth-eaten rags look couture). He sets the tone with the opening scene, in which various characters lip-synch prerecorded dialogue delivered by voices that are clearly not their own, immediately laying the foundations for the main narrative, which explores the idea of how we instantly make value judgments based on speech patterns. In typical, dynamically tricksy Headlong fashion, the era becomes arbitrary: ha’pennies and guineas are referenced, but taxis and handouts are paid in contemporary sterling; Shaw’s original script is littered with references to celebrities and all manner of 21st century slang; Eliza wears a jumpsuit that could have been bought in New Look to the garden party at the palace; and so on. Meanwhile, wireless headseats, handsfree microphones, a slick, hilarious hip-hop interlude, sampling and video sequences are all deployed to make us think, think and think again about exactly how we listen to the sounds we hear coming out of a person’s mouth, and fluid, sparse sets offer suitably modernistic backdrops that, though sparklingly innovative, never detract from the action.

At the core of the proceedings, Natalie Gavin is a fabulous modern-day Eliza Doolittle: a feisty survivor, frustrated by the constraints of poverty and neglect, vulnerable yet tenacious, and raging against a machine operated by male oppression. Playing opposite her, rather than merely being the misunderstood professor/eccentric patriarch as portrayed by Rex Harrison in the film version, Alex Beckett as Henry Higgins brings out the best and the worst in both his own complex character and Eliza’s: a socially and emotionally inept, academically brilliant, arrogant yet deeply conflicted misogynist. It’s left to Higgins’ friend Colonel Pickering to both unite, divide and generally referee the pair as the bet on Higgins being able to turn Eliza into a ‘lady’ gathers pace, and Raphael Sowole does all that’s required of him with panache: he may be a genial, sensitive cohort aiding and abetting the action, but his sensitivity is far more powerful than Higgins’ emotional brutality.

If you’re in search of a gentle, non-challenging night out at the theatre, you most definitely won’t get your cosy-up fix with this gloriously original mash-up of a longstanding British theatre classic. If, however, you fancy taking in an astutely relevant revival that reminds us there’s far more profundity in what people say, rather than how they say it, you’re in for an uncommonly posh night out.