In May 2002, Roy Keane got on a flight home from the South Pacific island nation of Saipan. It sent the people of Ireland into a football-induced psychosis that made Beckham's 1998 red card look like an incorrectly adjudicated corner in a midweek friendly. Keane, then the captain of the strongest Republic of Ireland team in living memory, had fallen out with manager Mick McCarthy, and deserted the shoddy training camp that had been set up ahead of the World Cup hosted by Japan and South Korea. In my homeland, all anyone talked about - on the radio, on the TV, in pubs - for literal years was this incident, not least because the team crashed out against Spain in the last 16. Could Keano have taken us further? It is the ultimate sliding-doors moment in Irish sport.

Despite this being a core memory of my childhood (I was 12 at the time), I have always felt that the rest of the world has little interest in the story. Taking the time to explain the fascinating depths of it to non-Irish people felt like wasted energy. So the existence of Saipan, a new movie that richly dramatises the whole thing, feels like a fever dream. Incredibly, McCarthy is played by Steve Coogan(!), while Cork-born up-and-comer Éanna Hardwicke (who played Connell's mate in Normal People) takes on the unenviable task of embodying the singular and slightly terrifying Keane. It manages to show the conflict in all its chewy glory - two hard-headed football lads with different ideologies butting heads, with disastrous consequences. Saipan may well be the nichest football movie of all time, and you know what? Good! More, please. Catch me in line for the Kieron Dyer versus Lee Bowyer on-pitch scuffle movie in 2029.

Ahead of Saipan's release, I got Hardwicke on a call to discuss taking on a sporting icon that would have loomed large in his childhood, picking sides in a 20-plus-year-old debate, and what he learned about Keane in the process.

GQ: Do you have any memories of the whole Saipan incident kicking off?

Éanna Hardwicke: I have a very vague memory of this scandal - I was maybe five going on six. I had no idea what it was about. I just knew people were pretty irate about it and it had something to do with Roy Keane and Mick McCarthy. I suppose most of my memories come from all of the incarnations in the few years after. It just seemed like for a good solid decade there, it was one of the main subjects for satire and comedy and pub conversation [in Ireland].

You grew up relatively close to where Keane grew up, right?

Yeah, Roy's from Mayfield, and my family lived in Glanmire - it's kind of like a suburb of Mayfield. So I would pass through there every day.

What was your initial feeling when this project came to you?

I kind of went, "I don't know if I'm your guy." I probably tried to talk myself out of it for a little while.

Why was that?

The Roy that we know has an incredible drive and an incredible tenacity and rigour to everything he does. And I felt I could do that, but I was daunted by the prospect. I think self-assuredness is one of those qualities that, if you don't really feel it or embody or capture it, that gets revealed on screen.

What made you change your mind?

I prepped and did the meeting. It was one of those wonderful moments where I'd never met co-directors Glenn [Leyburn] and Lisa [Barros D'Sa], [but] their vision for the script took it in a whole other direction that I hadn't really foreseen. They talked about it like a shipwreck drama, a sports drama, a sort of state-of-the-nation drama. I just thought, that sounds so original.

I imagine you probably had your own preconceptions about Roy Keane before going into the project. Did researching the project and playing him reveal anything surprising to you?

I was a very big fan of Roy's going in, and I would say only more so after. I think that quality of putting yourself in difficult situations and trying to perform at your best is one of the definitions of courage and bravery. It requires going through discomfort, whether that's playing through when your body is letting you down, when you're tired and fatigued and you're injured, or whether it's playing in an imperfect kind of scenario like the Saipan situation.

Did you reach out to Roy about playing him?

I didn't in this case. It can be very helpful to talk to the person you're playing. [But] I had a sharp sense that this was not going to be a biopic, it was going to be about this event. I had everything I could have needed to go on, because it was so widely documented. There were two or three interviews given by Roy during the time. He's written about it in his books, other people have written books about it.

I liked that the movie didn't really try to steer the audience toward one side - it felt balanced, like both Keane and McCarthy have their reasons for how they behaved.

Mick, as I understand it, is someone who loves the game and loves leading and managing a group of men. And there are some scenes in this film where you see Steve playing Mick, [and] the way he interacts with these players and carries himself on pitch just reminded me of why I fell in love with football and loved playing as a kid. That it's about something bigger than just the drive to win.

And then you've got Roy's quite ruthless, straight-as-an-arrow drive to win, which is also a wonderful quality. When I saw the finished film, I could see both of those elements in it, [and] I just felt very happy and bittersweet. Because obviously that was the best showing we've had in a World Cup, and it brought so much joy to the nation, and then also so much 'what could have been'. I still haven't found the words to articulate this, but there's something quintessentially Irish about that to me, just how I feel about being Irish. And it's sad, it's disappointing, but it's also kind of wonderful.

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