The cast of Derry Girls on series 2: Bill Clinton, boys and belly laughs

It is the most watched TV series in Northern Ireland since records began in 2002, and yes, we’ve checked the veracity of this statement. Their faces are immortalised in a ten foot high mural on the wall of a pub in the Northern Irish town centre - an accolade commonly reserved for political heroes.

But Derry natives Saoirse-Monica Jackson and Jamie-Lee O’Donnell, and blow ins Nicola Coughlan, Dylan Llewellyn and Louisa Harland (a Galwegian, a Brit and a Dub), haven’t let it get to their heads. In fact, they’re humbled and surprised by their newfound fame. “It’s just strange to think I’ve done something that’s worthy of a mural,” O’Donnell, who plays Michelle, tells RadioTimes.com ahead of the launch of the hotly anticipated second series.

Derry Girls is a traditional sitcom done exceptionally well, with an unassailable joke hit rate, aided by big performances from the core quintet and a cast of excellent supporting players that includes Irish comedy legend Tommy Tiernan and The Fall’s Ian McElhinney. It feels particularly relevant given the constant chatter about Brexit and the Northern Irish backstop in 2019, and the confusion that quietly surrounds it.

But its success was not always assured. At a recent BAFTA screening of the first two episodes of the new series, Channel 4’s director of programming Ian Katz admitted that history had made him doubt the show’s chances at success ahead of its premiere early last year.

“Traditionally, if you put The Troubles on the telly, the ratings fall,” he said.

He was pleasantly surprised. It was the station’s biggest comedy launch in 14 years, and its success has been reflected with a pride of place time slot for its second series, which will debut at 9.15pm on Tuesday 5th March, after The Great British Celebrity Bake Off.

“We always knew that it would resonate at home and that people from the south and the north would love it, but never did any of us expect for it to land so well over the water,” the show’s lead and top facial contortionist Jackson, who plays the group’s de facto leader Erin Quinn, says.

This is all down to the approach, which puts comedy at the forefront and gives us a realistic vision of what life was like for those growing up in a period of widespread violence and political turmoil. The girls deal with issues relating to The Troubles each day - in one season one episode, opting to leave the county to avoid the protestant Orange Order marches - but they’re far too wrapped up in their own issues to get bogged down by it.

“The joke of the show [is] that we are so concerned with ourselves, and the biggest thing that’s happening in our lives is I’m stealing [Erin’s] diary when actually the horror is going on in the streets and we ignore it,” Louisa Harland, who plays Erin’s quirky cousin Orla, says. “What [creator Lisa McGee] has done is just write the way that Northern Irish humor is,” Coughlan, “wee” goody two shoes Clare in the show, says. “The light and the shade coexist so clearly.”

“I was in Belfast recently and the cab driver was like, ‘how do you like Northern Ireland?’ And I said ‘I love it here’, and he was like ‘oh yeah we love other people, we just used to kill each other’. And then he was like, ‘that’s just our sense of humour’. It’s so dark.”

Jackson adds: “I think it’s a good reminder that nobody wants to go back to the way we were then.”

It has also proved educational, even for its own stars. Llewellyn, the sole Brit in the gang, admits he was completely unaware of Northern Irish history before starting the series.

“My character James is like the British ticket into the show, and to see it from his perspective of what Derry life is like and what Northern Ireland is like,” he says. “They don’t teach it in British schools, which is a shame I think ‘cause we need to know that sort of thing. I got a really broad view of it all. And seeing all the murals and everything in Belfast and Derry and all, it’s like wow, this stuff happened.”

Series one was such a runaway hit, garnering almost universal critical acclaim, that you’d forgive them for feeling a little bit nervous about the follow-up, but there are no sign of second album jitters. Having enjoyed the first two episodes with an audience full of typically reserved journalists who erupted with laughter every 30 seconds or so four 50 minutes straight, I can attest that the quality arguably surpasses that of the first run.

The cast’s chemistry is stronger than ever, thanks no doubt to the long press tours and shooting days spent in one another’s company. Plus, they’ve got a few aces up their sleeve, one of which has already been announced: Ardal O’Hanlon, star of Channel 4’s most beloved Irish comedy hit Father Ted, will guest star in one episode as a “mummy’s boy”. Father Peter (Peter Campion) makes a return in episode one, too - and there are more guest stars to get excited about, but they are keeping mum for now.

Paraphrasing her co-star Siobhan McSweeney, who plays Sister Michael, Coughlan calls it “the same [as series one], but it’s all in technicolour”. In other words, don’t expect to see the girls smarten up any time soon.

“I think Erin would like to see some progression in herself but I’m afraid she’s still really selfish, still a bit of a dick,” Jackson says.

“You’ve got the advantage this time, you’ve got to do a bit of the exposition for series one obviously but then you know the characters already so you’re going in completely at a 100, you don’t have to build up to it,” Coughlan says. “ It just starts off with a complete gang. You’re gonna feel like you’ve got your five weird friends back.”

That said, there’s still quite a bit that in series two might come as a surprise.

“They’re in a slightly different stage of school, and there’s more of an interest maybe in boys this season,” Jackson says, and her point is confirmed in the season premiere, a “friends across the border” episode which sees the gang go on a retreat with a group of protestant boys.

This gives Llewellyn a chance to flex his comedic muscles a bit more, as he vainly attempts to make some male friends.

O’Donnell also confirms that a later episode will centre around then US President Bill Clinton’s 1995 visit to Derry, a major national event which has been heralded as an important step in the peace process.

“The Bill Clinton visit was crazy, and that whole episode is just crazy,” O’Donnell says. “The girls go to see Bill Clinton, so you can imagine what sort of… it’s not very straightforward as usual. They’ve got the crowds and they try to replicate the exact day as much as possible. We’ve got like the Derry walls in the background and we filmed it in derry which was so lovely.”

Harland says she's particularly proud of the show's female-dominant cast, which hit a milestone in the new series.

"I think when we were filming season 2 there was one day where we had 11 women speaking parts in one scene which has never been done in a comedy before," she says. "We’re so proud that it's a female-led show."

Whatever way you spin it, the Derry Girls (and boy) look set to have another great year, and when the dust settles after its run on Channel 4, it'll make its way over across the globe to leave its mark on a whole new audience. Such is the power of well-written TV.

“I got a message from a girl in India being like, ‘this is what it was like for me in a segregated area’ and all this stuff,” Coughlan says. “I think people underestimate audiences a lot, I mean something like Summer Heights High [a cult Australian mockumentary set in an outer suburb of Sydney], it’s like we never had a question whether people would understand that here. I think there’s a thing with certain teen shows to kind of dilute it or make it more palatable for everybody. And Lisa was like, ‘no no, this is what it’s like there’. And I think people respond to that cause it feels real.”

Derry Girls series 2 will premiere on Tuesday 5th March at 9.15pm on Channel 4