The Canterbury Tales, Gielgud Theatre, London <!-- none onestar twostar threestar fivestar -->

You don't often get the work of a 14th-century poet on Shaftesbury Avenue. True, this is Chaucer, and The Canterbury Tales have been seen in the West End before. But previous stage treatments have appeared intent on presenting his tales merely as more explicit medieval precursors of the Carry On romps. This two-part RSC version - skilfully adapted by Mike Poulton, brought to London by the producers Thelma Holt and Bill Kenwright - certainly revels in the bawdy. For example, the bedroom farce of "The Reeve's Tale" contains a fart-fest that makes the cowboys' baked-bean wind problems in Blazing Saddles sound like polite conversation. There's "swyving" and cuckolding and bare butts galore, one of the latter treated to a red hot poker in the "nether eye".

But ribaldry is only part of the story, which is richly presented in two full-length, largely self-contained sections and directed with great verve by Greg Doran, Rebecca Gatward and Jonathan Munby. One strength of the show is the variety of styles it finds to suit different narrative types, ranging from daft puppetry for "The Nun's Priest's Tale" about the preening Chauntecleer and Pertelote to eerie shadow-play for "The Franklin's Tale" about a wife's psychological unrest during her husband's trip abroad.

A crack cast, packed with personality, fall on the material with gusto and finesse, relishing the opportunities provided as the pilgrims on the way to Canterbury bicker and feud, using their self-revealing tales as weapons. Paola Dionisotti is superb as the Prioress, who always looks on the point of collapse with her prissy piety, and as a succession of crones. The West Indian lilt Claire Benedict brings to the Wife of Bath is a lovely way of refreshing our sense of the woman's laid-back raunchiness and humour.

Staged with vivid simplicity on a green sward with a single tree and some ingeniously adaptable props, the production is overseen by Mike Hadfield's amusingly furtive Chaucer. Though the character breaks into a very funny contemporary rap when delivering his story at the start of the second section, it's good that Poulton's adaptation remains remarkably faithful to the tone of Chaucer's verse, updating some vocabulary but preserving its sardonic irony.

To 30 September (08709 500 915): Part 1 on Monday, Wednesday and Friday evenings at 7.30pm and Thursday and Saturday matinées at 2pm; Part 2 on Tuesday, Thursday and Saturday evenings at 7.30pm