I had an uncanny sense as I watched Aran Murphy in Sky's soapy legal drama, War: "I have 100 per cent seen this young man before." Turns out I hadn't. Murphy, who stars alongside Dominic West and Sienna Miller, just happens to bear a borderline spooky resemblance - physically, sonically and spiritually - to his father, Oscar-winner Cillian Murphy. Thankfully for him, it's not the only thing they share. The younger Murphy, who is just 19 and landed the job on War shortly after his final exams at school, is also an excellent, understated actor.

This month, the first three roles of his career converge. In War and in Sharon Horgan's genius HBO series Youth, he plays eerily similar parts: moody children of divorce, lost in the mush of late adolescence. Then there's Klara and the Sun (out in cinemas on 23 October), Taika Waititi's film adaptation of Kazuo Ishiguro's dystopian novel, in which he supports Jenna Ortega and Amy Adams. But Youth is the crown jewel of the bunch. The show follows Alex (Horgan), a divorced mother who decides to finally start dating again once her son Ruarí (Murphy) leaves for uni, only for him to swiftly return after dropping out halfway through Freshers' Week. The show then becomes a buddy comedy of sorts, as the two of them try to navigate these new phases of life together.

Murphy brings warmth and empathy to Ruarí, who, unlike most Gen-Z depictions in middle-aged TV, feels like a real person. Ruarí has a dipshit of a dad and knows it, spends his evenings doomscrolling through TikToks about "semen retention", has no idea what he wants to do with his life after school, and is anxiously navigating his first sexual experiences. Horgan and Murphy have believable chemistry as a mother and son often at loggerheads. It makes for easily one of my favourite shows - and performances - of the year.

Last month, I spoke with Murphy - about his beginnings in acting, working with Horgan and what he's learned from his dad - over a coffee in Covent Garden.

Aran, I wasn't sure what accent you would have in real life - but it's definitely Irish. Did you grow up in the UK?

I moved to Ireland when I was seven.

When you moved back, did you have an English accent?

Yeah, I had a really strong English accent.

I'm about to have a baby here, and I'm having to wrestle with the idea of him not having an Irish accent.

I do think, though, there's anomalies, because I have a friend who grew up in Bristol his whole life and went to a boarding school there and almost sounds more Irish than me.

I guess it's just something you have to make peace with.

Yeah, and not let it define whether you're Irish or not.

Tell me a bit about your beginnings in acting. How did it all start for you?

I kind of always loved it in school and just loved performing and stuff. And then, when I was 11, I did this play called Hamnet with an Irish theatre company called Dead Centre.

Was this the Maggie O'Farrell...?

It's the same story, but it was before the book came out. It was kind of like a contemporary take on it. I was only 11 and that was really awesome to be able to do. And we got to go around the world with it and stuff. I don't know, it was just a dream for any 11-year-old. And then I did a small part in an Irish indie film when I was 12 - a tiny part, I was in it for five seconds. I was still auditioning, but I didn't get anything until I was 16: Klara and the Sun. And that was where it properly started again.

Did you finish the Leaving Cert [Ireland's version of the A-Levels]?

I did, yeah. I think I wanted to just complete it and just have it done. After Klara and the Sun, I kind of just said I'll do my Leaving Cert and then hopefully still get stuff after that.

What year did you finish school?

2025.

So you did that and then got these projects?

Yeah. I finished in June and then found out about War in September, and then Youth in October.

That's pretty full-on. They're similar roles in quite different shows - you're the troubled kid of divorce in both.

Yeah, what are they trying to tell me? [Laughs.]

You're really subtle in both of the shows - and both roles could be over the top in the wrong hands. They both feel like real people. A lot of big generalisations are made about your generation - you're on your phones all the time, and struggle to socialise. Did Ruari in Youth in particular feel accurate to you?

Something that was really familiar was some of the dynamics that he has with his mum. It's kind of scarily, eerily familiar in some ways. He doesn't have many relationships, but the way he formed the relationships that he has with his family I found really interesting, and fun to explore. It was also just really nice because I'd just left school, he had just left school and we were both kind of figuring it out in very different ways. I think it's quite a universal theme of people who- whether you go to college or not, you just leave this six years of education and then it's kind of like, "What's next?"

You and Sharon Horgan have such a great rapport in the show. How did that develop?

I was definitely nervous going in, because she's such an Irish icon. But I went to her house and I met her and we had a long chat and from that chat on, I was like, Oh, she's so awesome and down to earth, and was so open to any ideas that I had, any things I want to change - would always kind of consult me with, "Would an 18-year-old say this?" I think it makes you feel super included and it's a real collaboration. It's not autocratic. There's just loads of room to have new ideas and make mistakes.

What was it like working with Dominic West on War?

It was awesome. [He's] such a legend. It was a smaller part, so it was kind of like, I came on for two days here and there. And that was also nice to learn how TV works that way, more of an in-and-out kind of guy.

Growing up, what were you watching?

The two biggest names were probably Wes Anderson and Taika Waititi, actually. Both those directors, their body of work for a kid is... a lot of the films for kids, I remember having a pretty big impact on me. And I was lucky that my parents gave me a good education young, or conditioned me to enjoy that kind of stuff and just good music and good films.

Did your dad instil certain things in you - want you to watch certain prestigious things?

It would always just be like, when we sat down to watch a movie, he would pick the movie a lot of the time. I think he was slowly just nudging us in the right direction. It was never forcing it on us. We always loved all the films, so it wasn't that hard.

Do you have any memories of movies in particular that left a mark?

I remember watching - it wasn't too long ago, actually, I think it was maybe two years ago, but it was Scarecrow with [Al] Pacino and Gene Hackman. I think because when I was younger, I used to always ask my dad, "What's your favourite film?" And I remember that one coming up a few times. And then I finally sat down to watch it and it kind of just blew me to pieces. It's such a different Pacino performance.

What is your music taste like?

Oh, that's a big question. Well, last night I went to see a band called Spanish Horses, who just signed with So Young Records, and they're pretty fucking incredible. I was at Electric Picnic [festival] and I saw this Irish band called Child of Prague. And also this band called Victoryland, who are based in Brooklyn. My brother put me onto them. They're seriously good.

How do you feel about the being-in-the-public-eye side of acting?

I think because I kind of grew up with it a little bit with my dad, so I think it's kind of... I wouldn't say I'm very excited by it, but I guess it's just a part of the gig, and it kind of coincides with doing all right. So I don't know. I mean, I'll just try and keep my life as my life, hopefully.

It seems like your dad has it figured out in a way. I guess also just being in Dublin - a bit away from the noise - helps. People in Dublin, as far as I'm aware, are fairly respectful of his peace. Did you find that people were coming up to your dad on the street a lot?

Yeah, but I think, as you said, in respectful ways, I think they get it a little bit. And what I really like is, in Ireland, sometimes people will just - if they do kind of recognise him, they'll just say, "How's it going, Cillian?" Just as if they're his pal, which I think is really nice, and a sweet thing to do. And it's not invasive or annoying.

Does your dad give you advice on acting?

I guess kind of inadvertently, maybe. He does a lot of my tapes with me. But he always just says, "Trust your instincts." That's kind of his one piece of advice.

Did you go to film sets a lot when you were growing up?

I did go to a few, but I hear other people who have parents in the industry and they're like, "Oh, I grew up on sets." I didn't really grow up on sets, which I'm kind of happy to say. It was nice to be on sets and have it feel like a real new thing to me and having to learn it all. But yeah, when I was younger, I used to love it, just all the excitement around it, and the free sweets.

You're also in Klara and the Sun, which is out this month. With Taika Waititi being such an inspiration for you, that must have been intimidating to be on set with him.

It was intimidating for the first 10 seconds and then you're like, Oh, he's just lovely and funny and bubbly. So you're immediately kind of put at ease, because there's nothing uptight about him or too overly serious. He's just totally up for a good time and for play.

That was your first part, right? How did that feel?

It was pretty nuts. I was in fifth year [the Irish equivalent of year 11], and I kind of hadn't heard anything on the audition. And then they were like - it was January, and they were like, "Yeah, we want to fly you to New Zealand in two weeks." And I was like, "What?" So it was kind of like everything was just upended.

You had to skip school for a bit?

Yeah, but I worked it out, and I only kind of missed a month, because there was an Easter holiday break in between. So with the New Zealand factor and being on a set with Taika Waititi and Jen Ortega, Amy Adams, it was kind of just a head-exploding moment for any 16-year-old. And then you're in these beautiful south of New Zealand mountains - it was all kind of jaw-dropping. So it definitely took me a while to... well, I don't know if I ever adjusted to that. I don't know if one can ever adjust. My friends were like, "Look at this prick, just skipped school to go to New Zealand for two months."

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