Airing on Christmas Day, the special was confirmed earlier this year after much speculation.

More than 18 million viewers tuned in to the last special in 2019 and were left wanting answers after a Christmas cliffhanger.

With stars including co-creators James Corden and Ruth Jones en route to Barry Island, Sky News spoke to some of Barry's businesses about the show's impact on the area.

Jackie Rogers, owner of Hyper Value gift shop, said the sitcom had "put Barry Island on the map" and her business had seen a "huge increase" in trade.

"People come here to Barry Island just to see Gavin & Stacey. They're not coming for the beach and the lovely area and everything," Ms Rogers said.

"And some people even say they want to come here and move here and live here because they're so attached to the show."

'Cult following'

Louis Ross, owner of Barrybados, said the timing of the last Christmas special just before the COVID lockdown meant businesses could not immediately reap the rewards.

"We locked down three months after the last Christmas special aired so people didn't really get to experience the whole Gavin & Stacey buzz after it aired last time," he added.

"So as soon as we opened back up in 2021 or whenever it was, there was this huge boom and there was this whole new fanbase for Gavin & Stacey."

Jo Linney from Sofia Souvenirs said the imminent filming for the final episode was "very exciting" for the town and the show's "dedicated" fans.

"We get lots of tourists coming in, saying they've been researching online when they're going to be filming," she said.

"We get visitors from Australia, they're doing a tour of the UK and Europe and they'll make a special effort to come to Barry.

"America, Scotland - until I worked here, I didn't realise how much hype there is."

'Concerns'

But last time the show was being filmed in 2019, not all residents were pleased.

Some locals complained about road closures and being kept awake until the early hours.

County councillor Mark Hooper, who represents the area, told Sky News all filming companies do their best to be "good neighbours" but acknowledged some had "concerns".

"You want to be able to park your car outside your house and if there's a filming unit there it becomes difficult," he said.

"You don't want to be kept up late at night. But they're professionals who are doing this, I hope they manage that appropriately.

"And we're used to seeing these things. The Vale of Glamorgan more generally is becoming a film set for lots of things. Where I live, one of the Doctor Who episodes was filmed a few years back."

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With the series finally coming to an end this year, 17 years since it started, there are mixed feelings in Barry.

"Everybody loves Gavin & Stacey in Barry, especially the businesses, because it helps bring tourism to Barry," Mr Ross added.

"Long may it continue, I'd love them to do more. But this is the last one, it's going to be one last hurrah and we're all excited for it."