The moment James Corden and Ruth Jones got the green light for the Gavin And Stacey Christmas Special, they couldn’t wait to call the cast – but getting in touch proved difficult.
With the creators of the hit Welsh comedy now living on different continents, mapping out the new episode had already proved geographically challenging, relying on rushed transatlantic trips topped up with Facetime sessions.
Despite the show being away from our screens for 10 years, the pair had continued to text each other back and forth with ideas for characters, including one occasion where Jones wrote out alternative lyrics to Adele's hit Hello in the style of Nessa, kicking off with the word, "Alrigh?'"
However, it was only once the script for the special was written and the BBC were fully on board that Corden and Jones could finally approach the cast with the news.
But there was a problem.
Rob Wilfort, who plays Jason, and Melanie Walters, who plays Gwen, both admit they ignored the initial calls from America, assuming they were a wind up.
Wilfort explains: "I got this call from Los Angeles, it was James [Corden] but I thought it was a scam, like the Nigerian prince trick or something."
Walters agrees: "James text me. And the way he phrased the text was: "It's James Corden here Mel, you may remember me". I just thought I was being trolled. I just completely ignored it.
"Then he rang and it was a weird number, and so I completely ignored it again. It was around the fourth time, he actually left a voicemail, and I finally realised it was him."
Joanna Page, who plays Stacey, also totally failed to respond Ruth's messages, despite her calls coming from the UK.
"Ruth just got in touch with me on every form of social media, email, message, everything. And I'm not very good at getting back in touch with people, I'm absolutely terrible. So I didn't respond for a bit because I was busy with the kids."
The entire cast good-humouredly agree, "Joanna will never get back to you".
When she finally did respond to all the calls, voicemails, texts, and emails, she was "hysterical" with happiness.
So, finally getting the team back together for the shoot - including the majority of the original crew - was no mean feat.
It was in the interim, between saying yes to the role and starting the project, that nerves kicked in for some of the cast.
Page says she read through the script in a car park just before a read-through for another show.
"After the excitement came the nerves… I was so excited, then I thought am I going to be able to do it? Can I even act anymore?"
Alison Steadman says she was so nervous about filming, she watched clips of herself playing Pam on YouTube to "make sure she got her right".
The cast's worries are understandable, with the show accruing a wealth of hard-core fans after running for three series between 2007 and 2010, and graduating from BBC3 to BBC1 in the process.
The Christmas special catches up with the much loved-characters in a whole new stage of their lives: Gavin and Stacey now have kids (named with a touch of royal inspiration), Neil The Baby is now 11-years-old (and played by child actor Oscar Hartland who was one of the show's original babies) and Smithy and Nessa are a long-distance example of a 'blended family'.
Filmed in Wales during the height of the summer, Rob Brydon, who plays Uncle Bryn, admits his polyester outfit added to the pressure of the 17-day shoot.
"Bryn's trousers are a hundred percent polyester. His jumper is a hundred percent polyester. And his short sleeved shirt is a hundred percent polyester. Boy, I was sweating."
There was even a WhatsApp group named Gilbert and Sullivan, so as not to let on the true nature of the project.
Ruth Jones says returning to Nessa was "liberating", using her forthright character to keep the crowds in check during filming.
Getting back into costume, including one of Nessa's original leather skirts, she explains: "I just absolutely adore Nessa, because when I'm playing her, I just feel so brave."
And she used that feeling to advantage on set: "When we were filming, and needed everyone to be quiet, I was able to go out there and as Nessa and yell: 'Oh, we're trying to film in there, now come on. Have some respect'."
As for working alongside Corden again, she says she loves him with all her heart: "We can argue, don't get me wrong, we have a very brother and sisterly relationship, but our friendship at the heart of it is so strong.
"I am so proud of our friendship and the journey that we've been on together."
And observant fans, eager to see the show back on the screen, will be rewarded with plenty of 'Easter eggs' throughout the special.
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While Gwen's renowned omelette might not get a mention, it does make an appearance.
A quick-glimpse at Nessa's wrist during another scene also reveals a tattoo in honour of Neil The Baby.
There's also a tantalising possibility that there could be a final reveal, exposing exactly what happened on Bryn and Jason's infamous fishing trip.
Or maybe not.
In a touching tribute, the one-hour episode is dedicated to actress Margaret John, who played Doris in the show, but died aged 84 following the third series.
The one-hour Gavin And Stacey Christmas Special will air on Christmas Day at 8.30pm on BBC1.