Do Americans understand irony? Let's have a heated debate!

Caroline Aherne was not convinced by my bright idea to record three episodes of The Mrs Merton Show in Las Vegas. She was fearful that it might not work so far from its Manchester home, and without the regular hand-picked audience.

Then let's take the audience with us, I argued. And on the back of such executive bravado (and a BBC cheque) 50 pensioners from the North-west with an average age of 70, set off for Buggy Seigel's famous "Flamingo" hotel.

Top idea it may have been, but this little tale is a reminder of how television is so frequently produced on the thinnest of margins between success and failure.

Our intrepid pensioners had a rough ride out. They got delayed at Newark, New Jersey when 15 appeared not to have been booked on the plane, and then were stuck in Cleveland, Ohio for a further eight hours due to a snowstorm.

But they arrived at long last in good spirits and, despite jetlag, were ready to support Caroline on the first show the following day. LaToya Jackson and Tammy Wynette were the guests and we had invited 50 local pensioners, all of whom had seen tapes of the show, and been schooled in the ways of Mrs M. They arrived full of enthusiasm.

Our audience is crucial to the show's success. Many have become minor celebrities in their own right, such as Roy, the colourfully dressed ex- roadsweeper, who boldly told Lorraine Kelly that he'd like to crawl into the TV and give her one "of a morning", or Horace the former car-tyre salesman who told Boy George all about his experiences in a Manchester sauna, when a fellow dry heat enthusiast suddenly died from a heart attack. Then there are the three Wigan ladies, Enid, Sylvia and Liz, who are forever tying to lure the hunkier guests like Daniel O'Donnell and Des Lynam back to their place.

The notion of a regular audience was never planned, but had developed from the pilot show in 1994 when the production team had been so desperate to fill the studio that they had forced all their "old" relatives, neighbours and friends to turn up. They all had such a good time they kept coming back.

By the end of the second series the spontaneous contributions from the audience in the "heated debates", had become such an original and funny part of the show that we had cut the guests from three to two to accommodate more of them.

But while Caroline wouldn't have contemplated the Las Vegas shows without her faithful ageing posse, their presence couldn't prevent the problem that developed.

Caroline woke up on the morning of the first show with what is commonly described as Las Vegas throat, caused usually by the combination of dry climate and air conditioning. She sounded very odd, neither able to talk recognisably as Caroline or in character as Mrs Merton. There seemed no medical remedy that could make her sound better. Yet the show - of course - had to go on.

It was immediately apparent however, that Caroline's odd voice, her Mancunian accent and the very boldness of the show was not going to bridge the cultural divide. The Americans watched in deepening bafflement - 50 stony- faced pensioners supremely uncomprehending of the show's most vital ingredient - irony. Matters quickly began to take a dramatic turn for the worse.

With our 50 regulars sitting on one side, and the 50 Americans on the other, Mrs Merton welcomed LaToya, and explained that her throat "was buggered by a load of phlegm". "Did your brother Michael", she went on, smiling sweetly "ever find that other glove?" Manchester laughed. Las Vegas didn't.

The Americans sat with deepening incomprehension as she asked about a typical Jackson family gathering. "There's you, there's Janet and there's Michael in his oxygen tent - lets be honest he's not a full shilling is he?" Again, laughter from the UK and deafening silence from the US. Yet when LaToya offered the standard American chat-show platitude, "We're a typical American family, no different from any other," it was the Mancunians turn to fall silent, while the home supporters erupted into enthusiastic loud applause.

Then Caroline introduced Mrs Merton's fictional son Malcolm. Her co- star in the British Gas ads (where he's played by one of the senior writers, Craig Cash), Malcolm is familiar to regular viewers as "a bit of a problem" son. During the last Christmas special, Mrs Merton told Noddy Holder that Malcolm liked to take his friends up the Gary Glitter - a shocking and intimate revelation that few of the audience really understood. And it was this theme that reappeared with LaToya.

"Your brother Michael," Caroline enquired, "he's always touching himself down below. What's all that about?" LaToya replied stiffly that she would have to ask him herself. Caroline battled on: "Well, my son Malcolm went through a phase of touching himself downstairs. Well I think they all do don't they?"

LaToya stared at her unsmiling. "Well we got some cream from the doctors but it just made the problem bigger," Mrs M concluded with a little laugh. Innuendo, like irony, is another piece of comic armoury that Americans don't expect in a chat show.

The downward spiral continued with Tammy Wynette. Caroline's voice was getting worse, and her confidence was rapidly fragmenting as the Americans chatted loudly among themselves, or headed for the door. Eventually the recording ground to a halt. It was clear that the show was untransmittable.

A doctor ordered rest and gargling with salted water. The future of the next two shows hung horribly in the balance. A priest who had travelled out with the Manchester pensioners led a mass in the local Catholic church to pray for her recovery. And God, it seemed, was listening.

Her voice miraculously returned, and we whittled the American pensioners down to 12 and mixed them up with our regulars. It worked like a charm. The next two shows went down a storm. Tony Curtis so enjoyed himself he thanked everyone in the audience individually. Seeing a Hollywood Legend take the time to do this was wonderful and made it all worthwhile.

Andy Harries is the Controller of Comedy at Granada Productions. 'Mrs Merton in Las Vegas' goes out on BBC1 on Thursday at 10pm