She appeared in just one scene of Gavin and Stacey, but Catrin-Mai Huw still gets recognised for her role in the show.
Huw played Stacey's enemy Natalie Lewis, whose dad and brother - according to the script - once had a fight with Nessa.
Stacey and Natalie have a 32-second stare-off in a pharmacy, only interrupted when a customer asks Natalie: "Where to's your fake tans?"
It's one of many relatable moments that have caught the hearts of fans of the much-loved sitcom.
Now a teacher, Catrin-Mai Huw says some people still quote the pharmacy scene when they see her - including her own pupils.
"I think a few years ago they'd done a meme out of that scene," said Huw, 36.
"So I had several pupils saying 'miss, can I show you something on my phone please?'"
Huw said the single scene, filmed in a day, was "really simple".
"There's hardly any dialogue but it's fun," she added.
"But because it's literally one scene, it is funny how people still recognise me 15 years later!"
When William Thomas was approached for a part in Gavin and Stacey he already had an impressive acting CV, with previous roles including Only Fools and Horses.
But he was taken aback when he saw the details of his first appearance as the eccentric vicar Father Chris.
“I saw this five page scene and I thought ‘crikey’,” Thomas recalled.
Now the stuff of legend among fans, the scene involves Father Chris demanding to know his parishioners' favourite sandwiches.
When Gavin says he doesn’t “see the point”, Father Chris explodes: “You don’t see the point!? Well, I’ll tell you the point, you jumped up little…”
Thomas said he was "incredibly nervous" filming the scene in front of "all the names", including Ruth Jones and James Corden.
“[But] there were laughs coming from the congregation, so I thought ‘well it seems to be working’.”
Thomas, 78, had two more appearances as Father Chris for the christening of Baby Neil and the wedding of Nessa and Dave.
“I don’t think anybody expected [Gavin and Stacey] to be as big as it is – my wife and my son are absolutely obsessed with it," he said.
Does he think Smithy will accept Nessa’s proposal?
“My instinct says yes he did actually, because I think there’s a very deep affection and love there,” Thomas said.
“But he probably won’t say it right until three minutes from the end!”
Steven Meo’s role as Gavin’s new colleague, Owain Hughes, left viewers of the show scratching their heads.
“Hi, nice to meet you. [I’m] Gavin Shipman,” Gavin tells Owain, shaking his hand, after starting a job in Cardiff in series three.
“Owain Hughes,” responds Owain, adding: “And before you ask, no I don’t!”
The apparent joke prompts laughter from Owain and the boss, while Gavin looks baffled.
What did the joke mean?
According to Meo, absolutely nothing.
“It is literally just a red herring designed to wind people up,” he revealed.
“A great bit of the comedy in Gavin and Stacey comes from the differences in cultures between Wales and England, and I think that was just Ruth [Jones] playing a little joke," Meo added.
“The amount of people you see online going ‘no I know what it is, I’m Welsh, I know what it is!’
“[But] it was literally just to throw a curveball.”
Meo, who is currently starring in a West End production of Fawlty Towers, still gets recognised for Gavin and Stacey.
“Whenever I do anything new on TV there’s always an article that reads ‘Gavin and Stacey star unrecognisable in new role’, and I kind of want to say ‘it was 15 years ago mate!’”
Meo credits the quality of the scripts for Gavin and Stacey's enduring legacy.
“There’s a lot of love, a lot of hope and a lot of redemption,” he said.
“It’s essentially a feel good comedy with really endearing characters and really endearing family units, and you root for them.”
Dic Powell, who sells stolen goods and speaks only Welsh, appeared just twice throughout the series.
But the actor Gwynfor Roberts, who portrays Dic, said his character was "kept alive” by numerous script mentions - including when Bryn tells the Essex contingent Dic is the “one man in Barry that speaks Welsh”.
Dic’s standout appearance is in series three, when he sells stolen barbecue meats to Mick and Bryn.
He lists off the items for sale in Welsh - including “kebabau” - before Mick says the products “look like they’ve fallen off the back of a lorry”.
“No Mick!” replies Bryn. “It's not fallen off the back of a lorry. It's been stolen!”
Roberts, who worked on the Welsh soap opera Pobol y Cwm for nearly 40 years, said he still gets recognised for his role as Dic.
“It has happened on numerous occasions to be honest, especially as I live in Barry anyway,” said Roberts.
“I was stopped once outside Marco’s (cafe)… it was quite a youngster, late teens or early 20s, who sort of did a double take and said, ‘are you Dic Powell’s double?’”
Roberts said he would definitely be watching the finale on Christmas Day.
“It’s sad when anything comes to an end and they call it a day, but it’s good that they’ve decided to do a final episode I think, so that they can answer a few unanswered questions,” he said.
“Although, I don’t think they’ll answer the fishing trip one!”