Mrs Brown Rides Again, Hammersmith Apollo

There's a great PhD to be written about why comics are so keen to dress as old biddies, from Arthur Lucan and Benny Hill to Dick Emery and Les Dawson, by way of any number of panto dames to the most noble of them all, Dame Edna Everage. To this esteemed list of comics should be added Brendan O'Carroll, whose Agnes Brown is an astonishing creation, a foul-mouthed Dublin widow whose passions in life are bingo and poking her nose into her children's lives.

Mrs Brown first saw the light of day on radio in Ireland in 1992 and then in a series of books. In 2000, one was adapted into a film with, remarkably, Anjelica Huston as Mrs Brown. O'Carroll (pictured below in character) then broadened out the stories for RTE television with many of the characters being played by his own family. The most recent version, a sitcom called Mrs Brown's Boys, is recorded in front of a studio audience in free-wheeling style, with cameras and crew sometimes in shot, and O'Carroll often going off script to wrongfoot a cast member or address the audience.

What matters here are the gags – verbal, visual and physical

It's unashamedly old-fashioned entertainment - with large doses of filth and swearing - and I was astonished when the BBC bought the show last year, but two series have been a huge success and DVDs sell by the truckload. Last month the show won the best sitcom BAFTA, which stands proudly on the set of the touring show.

Mrs Brown Rides Again is an amalgam of stories from the TV series and has little by way of a dramatic structure; what matters here are the gags – verbal, visual and physical, which come thick and fast, and are often hilariously bawdy. When a heavy breather rings the house, Mrs Brown's daughter Cathy (Jennifer Gibney) answers the phone. “He asks can I guess what's in his hand,” she says. Her mother grabs the phone and shouts, “If it fits in your hand you can fecking keep it.”

Her children are planning a surprise party for her birthday and her ageing dog is ill. They suddenly stop speaking when she comes into a room but she overhears their whispering - “she's smelly and wees all over the place” - and thinks they are planning to put her into a home. Meanwhile the boyfriend of gay son Rory - “I love you but I'm still hoping for a cure” - announces he wants them to have a baby together, Cathy brings home her condescending academic boyfriend and another son, Dermot, cooks up a raffle-ticket scam with his moronic mate Buster. There are gags galore, involving bikini waxes - “It's only for the craic” - condoms, childbirth and heart attacks, and O'Carroll slipped in some neat jokes about the Jubilee and Euro 2012.

In a theatrical setting, the shortcomings of O'Carroll's supporting cast are all too obvious and there's far too much corpsing, a lot of which looks rehearsed. When he's not on stage the energy instantly drops, and when he is some of the cast just stand around waiting for him to make a funny. But Gibney (O'Carroll's wife) and his sister Eilish O'Carroll - as neighbour Winnie, the butt of many of the jokes - stand out.

The references to gays are horribly unfunny, the show's heavy-handed Oirishness makes me uncomfortable (indeed it's thoroughly disliked by almost all my Irish family and friends) and many of the jokes are so old you could supply the punchlines. But there's an undeniable warmth to this show and it's filled with big laughs because of O'Carroll's superb clowning.

• Mrs Brown Rides Again is at Hammersmith Apollo, London W6 tonight and tomorrow, then touring until 17 December