Rob Brydon In The Keith Barret Show Live, Alban Arena, St Albans

That the Alban Arena has the feel of a plush school hall is quite appropriate for a seminar on divorce. However, there's nothing particularly academic about the hopefully titled, "Making Divorce Work", and it's far from a fusty affair with Rob Brydon's comic creation, Keith Barret, covering every corner of the theatre by the end of the show, leaving a trail of mirth as he goes.

A constant stream of latecomers was the basis for much of Barret's introductory banter tonight. "Have you been dogging in the car park?" he says to two couples as they take their seats; and to another man he quips: "wearing a tracksuit and you're still late!". It's not highly original but it is effective. Moreover, his ability to get near the knuckle with an audience made up of middle-aged married couples is admirable.

So, perhaps not as many divorcees as Barret, the cuckolded ex-cabbie of Marion & Geoff fame, would have liked for his presentation, but his real centrepiece is an interview with a married couple. On The Keith Barret Show on television, it was a celebrity couple, on tour it's Joe and Joanne Public. Under questioning, the resulting coyness and embarrassment is a great leveller and so there's no less entertainment here than there was on TV with Richard Madeley and Judy Finnegan or Lembit Opik and Sian Lloyd, for example. In fact, Diane and Ken, two local teachers recently married but late on in life, provided warmth and hilarity beyond expectation.

"I'm so glad I can't see you all," said Ken looking out from the stage. "Why, have you got cataracts?" countered Barret. When the questions for the couple opened out to the audience, one girl asked: "How do you keep your sex drive alive?". Before re-introducing the question to them, Barret qualified: "First I have to ask, do you keep your sex drive alive?"

As our host himself says, "it's a bit of fun". The show is never really prurient but then again no punches are pulled in matters of taste. For example, earlier in the show Barret points out that Countdown host Richard Whiteley's affliction of pneumonia is, at least, a nine-letter word. This delighted and revolted the audience in equal measure. Under protection from his naïve alter ego, a man who disdains "potty mouths" and drinking, Brydon can get away with such forays into bad taste.

Tours to 17 July (www.robbrydon.com)