Ahead of the first series of Mrs Brown's Boys in a decade, Brendan O'Carroll tells Rachael Davis about family feuds and his 'extraordinary' mother.

For the last decade, fans of Mrs Brown's Boys have delighted in the fleeting festive appearances from their beloved Agnes and her family, but now - for the first time since 2013 - there's a brand new series coming to BBC One.

Creator and star Brendan O'Carroll, 67, has penned a four-part miniseries of the popular comedy, which centres around Irish mammy Agnes Brown and her large family.

This series, fans will see how Agnes copes with a bout of depression, what happens when she tries speed-dating, how she contends with potentially being a lottery winner, and what happens when she has to organise a wedding.

Recorded in front of a live studio audience, the Mrs Brown's Boys experience is raucous and mischievous, with the fact that the cast comprises many members of O'Carroll's own family adding to the heart-warming hilarity.

Returning to Agnes and writing a full series of Mrs Brown's Boys "felt like a rebirth", O'Carroll says.

"I don't find it hard to switch to being Agnes, not to be Brendan, to be, 'Hello son, sit down, sit down and talk to mammy, come on'," he adds.

"Getting ready, putting on everything, put on the mole - as soon as the mole is on, I put on my glasses, and there she is.

"And I even unconsciously find myself (putting) on the glasses and go: 'Oh, hello, there you are'," he says, switching into Agnes's feminine, Irish lilt.

Describing his return to Agnes as a "rebirth" is - not to get all Freudian on the matter - an interesting word choice on O'Carroll's part.

As he relaxes into our chat, puffing away on a cigarette and descending into an insightful stream of consciousness, the comic - who's been working on Agnes in a variety of capacities since the early 1990s - reflects on how despite his denials over the years, his character might well be based on his own mother after all.

"Particularly when I did book tours in America with the books, people would always ask, 'Is Mrs Brown based on your mum?' And I used to say, no, no, she's not," he says.

"Because my mum was quite extraordinary. My mum started her life as a nun, and then went on to have 11 kids. So she wasn't meant to be a f****** nun, that's for sure!"

O'Carroll's mother, Maureen, went on to become a politician, serving as the Irish Labour Party's chief whip, the first woman to hold that position in any Irish political party - "an extraordinary woman", he reiterates.

"So I used to go, 'No, no'. But actually, the longer it goes on, I start to realise, Agnes is my mum, but without the education my mum had," he continues.

"My mum had a great education. Agnes didn't, but she has the wisdom. And she has that turn of phrase - mum would have a turn of phrase for everything, but Agnes has that turn of phrase that she doesn't always get right - 'Well, that's the way it goes, the cows come home to roost'. But you know what she means, and she knows what she means.

"I think the freedom of being Agnes comes from, I learned a lot from my mum.

"I'm the youngest of the 11 kids - she was 46 when I was born. By the time I got to formative years, the other family had either emigrated or got married. So I had the uninterrupted attention of this genius of a woman. So I soaked everything up from her.

"I know that my sisters and brothers, when I talk about my mother, they have no idea who I'm talking about, and when they talk about my mam, I've no idea who they're talking about.

"They talked about a woman who they heard on the radio decrying the fact that children were coming out of school still illiterate, but wasn't there to help them with their homework. (Whereas) I got 100% attention, she'd retired, you know, she was ready for me.

"I think Agnes is that kind of mother that if one of her sons murdered somebody, she would be devastated. But she would help them hide the body. She would do anything for her kids. She'd even take the rap.

"You know what, maybe that was the mother that I wanted my mother to be. How deep are we f****** going now?"

Aside from the connection with his own mother, O'Carroll says there are so many things he loves about playing Agnes - which is just as well, seeing as he has dedicated his career to the character.

"A 70-year-old woman gets away with things that I would never get away with. She just doesn't care," he says.

"She absolutely doesn't care. I think you get to that age where all the stuff that you thought was so important is just trivial shit.

"I like that she's trying her best. You know, she wants to support the LGBT community. But she doesn't actually understand, even though she has a gay son, she doesn't really understand what gay is. But I like that she wants to support these things.

"I like that she adores her kids. She absolutely adores her children."

Family is, as ever, at the heart of Mrs Brown's Boys, with the extended O'Carroll family coming together again for the new series, including, but far from limited to: O'Carroll's wife Jennifer Gibney as Cathy; his sister Eilish O'Carroll as Winnie; his daughter Fiona O'Carroll as Maria; and his son, Danny O'Carroll, as Buster.

"It's not hard to work with them, they're all very pro," he says when asked if he feels lucky to work so closely with his family.

"We have the normal rows - trust me, we have family f****** feuds within the camp - but it's never, ever brought on stage. It's never, ever brought onto the studio floor.

"And you know, being on stage every night also helps. Because all of a sudden you gotta leave that behind you, and sometimes you're in the middle of your show and you go, 'The f*** is wrong with me? It's not that serious'. And it heals an awful lot.

"So I suppose you could say the family that plays together stays together."

Mrs Brown's Boys returns to BBC One at 9.30pm on Friday September 8.