Since the first staging of Willy Russell’s hilarious two-hander Educating Rita by the RSC almost 30 years ago, the play has never been out of production somewhere in the world. I learned this from the programme at the Watermill Theatre, near Newbury, where the latest revival is delighting packed houses (until November 14).

The popularity of the play is not hard to fathom. Not only is it extremely funny, which always helps to place bums on seats, but it is also rooted firmly in reality, a fact that audiences are known to respect. This is a story inspired by Russell’s own attempt to acquire an education later in life, having given up school (or it him) at the age of 15. Why, he even started out, like Rita, working as a hairdresser, which explains the delicious observations in the play about the pursuit of this craft among the ladies of Liverpool.

The joy of the action comes from seeing the Eliza Doolittle-like transformation of Rita from a gabbling airhead – as she first seems to be but clearly isn’t – into a brainbox able to spout Eng. Lit. theories with the best of them.

In fact, the play contains more than a suggestion that shambolic, but inspirational teacher Frank has helped to create something of a monster. As the drama proceeds in a series of shortish encounters in Frank’s book-filled university study (excellently created by designer Andrew D. Edwards) one rather starts to feel that the breath of fresh air that Rita brought on her first appearance has started to become an uncomfortable, hard-to-control gale-force wind. The reference to Mary Shelley, author of Frankenstein, among many other literary luminaries (including Blake, Lawrence, Hardy, Forster, Maugham and, of course, Shakespeare) is hardly accidental.

There are many bookish in-jokes, incidentally – more hits among them than misses. Concerning Forster, for instance, a spoof examination question is offered: “Does his repeated use of the phrase ‘only connect’ suggest he is a frustrated electrician?” And, as for the American poet Ferlinghetti, Rita muses that she had always thought this was something one had with grated parmesan.

Pupil and teacher are both given strong performances here, under director Jamie Glover. Claire Lams perfectly suggests Rita’s eager curiosity and frustration over her as-yet-unfulfilled life, while Tim Bentinck – well-known to fans of The Archers for his role as David in the long-running radio soap – subtly suggests the tendresse Frank quickly starts to feel for his lovely student as well as his suspicion that hers is a questing, lively mind which might develop more successfully without the rigours of academic discipline.

That Frank is not entirely up for change himself is early revealed in his attitude to booze. Having been quizzed by his angry partner on the telephone over whether he is still determined to go to the pub, he tells Rita: “I don’t need determination to go to the pub.” This struck me, like so much else in this play, as being very neatly put.

Box office: Tel: 01635 46044 (www.watermill.org.uk).