For the past 40 or so years it’s been a two-way duke out between Bob Geldof and Dave Fanning, but now they’ve a serious rival for the title of World’s Fastest Talking Dubliner: actor, writer and dance music aficionado, Emmet Kirwan.

A well-kept secret until last year when his slam poetry state of the nation address, ‘Heartbreak’, amassed close to half-a-million views, Kirwan is all gesticulating arms and sprint-to-the-finish sentences as he talks to us about the big screen version of his much-lauded two-man play, Dublin Oldschool, which goes on general release this month. His enthusiasm is well placed. As frenetic as it is powerful and thought provoking, the film finds the Tallaght thesp joined on screen by a veritable who’s who of emerging Irish acting talent. The ante is further upped by the soundtrack of banging club tunes, including ones from Orbital, Sound Crowd, Slam, Rejuvination and Funk D Void that Emmet used to rave to himself as a teenager.

“I remember – or sort of remember - being at Creamfields and Homelands in the late ‘90s, and going to the Mansion House raves where Mark Kavanagh and Mr. Spring from Sound Crowd were regulars,” he reminisces. “We had a pirate station, Club FM, in Tallaght that did prisoner requests! I was into that early ‘90s hardcore and breakbeat: all the good stuff. Then there was this really weird stage when that Scottish gabba band, Ultrasonic, and Scooter, who were sort of nursery rhyme techno, were really popular. For me, it was house and yokes. I would have seen Dave Clarke and those Detroit lads like Derrick May coming through. Later on, with ketamine, it was all minimal techno. Drugs have always dictated what the music’s like.

“Cast-wise, yeah, we were blessed,” he continues. “Sarah Greene, who’s becoming a big international star, was over in London at the same time as me: I was writing bits and pieces in the National Studio and she was doing Woyzeck in the Old Vic. Whilst having a pint together she asked, ‘How’s the film going?’ and I go, jokingly because I know how stupidly busy she is, ‘Great: there’s a part in it if you want.’ She just goes, ‘Yep, sign me up!’ There actually wasn’t part for her, but we expanded the film to get her in! We were also really fortunate given her schedule to get Seána Kerslake who I didn’t know before but is such a great actor. Her character existed in the play as a poem, so I had to bring Gemma, who she plays, to life and give her a back story.”

The original Dublin Oldschool was, indeed, a very different kettle of ketamine. “I played three characters on stage and Ian Lloyd Anderson, who’s Daniel, played 29! The theatre piece goes through space and time to the actual molten depth of the universe. Joe pushes himself into these cosmic realms, which in the film have become flashbacks.”

Asked whether the endgame was always to turn it into a film, Emmet shakes his head and says, “No, it was David Tynan, the director, coming to see the play in Bewley’s Café Theatre – a great space – that acted as the catalyst. The producers, Dave Leahy and Mike Donnelly, met me then for a pint in the Bernard Shaw pub – another favourite of mine – and said, ‘Could you turn this into a movie in 18 months?’ I wasn’t sure I could but went, ‘Yeah, right!’”

The overt hedonism that characterised the Dublin dance scene back then didn’t stop many of its key practitioners going on to enjoy successful creative careers.

“Like punk, that underground scene opened the door for a lot of really talented people. Gav Collins who’s now Matador and Mano Le Tough were around back then, as were Little Dave who’s a successful manager; Al Keegan who’s into marketing and events; and Seamus O’Reilly who did that story about meeting the President of Ireland whilst on ketamine. They were all rave-era mates of mine.”

The Dublin Oldschool action focuses on Jason, a wannabe DJ and prolific ketamine user whose childhood woes resurface when he runs into Daniel, his estranged brother who’s living rough and battling heroin addiction after disappearing off to England. Wanting a cinéma vérité feel, Emmet and David Tynan opted wherever possible for shooting on the street with a hand-held camera.

“Here’s a good story!” he grins. “You know the scene in the alleyway? We were shooting that and a woman not realising we were actors came out and said, ‘Whatever that language is and whatever’s going on, I want you to stop right now!’ As soon as we explained who we were and what the film’s about, she was like, ‘Oh, great, I’m a drug addiction counselor, work away!’ This lady works with people nearby in Parliament Street. There’s a person in Dublin City Council who sorts things out and gives you the piece of paper you show the Guards in case they think the cameras are a cover for some sort of criminal endeavour! I know we portray them as sort of Keystone Kops in the movie, but the real life ones we encountered filming were actually grand.”

While Jason and Daniel are both composites, a lot of the other characters are people Emmet has partied with in the past.

“Yeah, there really was a guy who fell through the wall at a party and left a gaping hole in it, and a DJ, English Tom, who ran a night called Hospital who went to B&Q when it opened and got the plaster and tools needed to fix it.

“As for what else is autobiographical, I did have a meeting with my bro in London – I won’t go too deeply into it – which made me go, ‘OK, what would happen if I extrapolated from that moment and brought it back to Dublin for the course of a weekend?’ Then I thought, ‘We need the other brother to have an addiction that’s somewhat analogous to heroin – I know, ketamine!’ So I started writing a story about addiction and also the subculture of dance music in Dublin. Somebody said to me recently, ‘Are raves back?’ and I was like, ‘Mate, raves never stopped! Just because you hit whatever age and stopped going out doesn’t mean that kids aren’t making their own parties.’”

Music supervision duties fall to Johnny Moy, the Dublin DJ who’s rubbed slipmats in the past with the likes of Death In Vegas, The Chemical Brothers, Andrew Weatherall and Shit Robot whose ‘Teenage Bass’ also gets a run out.

“I was at God knows how many of his gigs back in the day,” Emmet recalls. “Johnny’s a genius when it comes to creating a mood or atmosphere with music. It’s a real talent.” It’s interesting that having turned down the equally gritty Cardboard Gangsters three times for funding – its star and director, John Connors, accused them of only being interested in “arthouse or some kind of tourist leprechaun thing” – the Irish Film Board were happy to stump up a decent chunk of the Dublin Oldschool budget.

“They sometimes go, ‘What’s the subject matter?’ and if it’s controversial it might not get past the first post. But I think the Film Board is generally far more risk-taking than any other funding body in the country. They’ve hit upon a vein of success and they know how to make movies and have them compete. Other bodies haven’t taken risks. I’ve slagged off RTÉ: Love/Hate was great but there’s boundaries to be pushed, especially in comedy and story-based narratives.”

One of the year’s televisual highlights was Emmet laying down the social justice law to Tubs – and any politicians who happened to be watching – on the Late Late.

“There are a lot of social issues and problems that the political classes say don’t exist because the economy and the GDP is up,” he proffers. “But that’s not indicative of the quiet desperation and quiet abject poverty that many citizens are living in. Having repealed the fuck out of the 8th, it’s drugs and housing that have to be sorted out. Dublin is a great city: people here look after their own, but there’s only so much they can do without proper leadership from government.”

As much as he’s enjoying his foray into film – the reviews so far for Dublin Oldschool have been universally positive – Emmet can’t wait to get back to his first love: theatre. “I’m doing Brian Friels’s Aristocrats, with Eileen Walsh and Elaine Cassidy at the Donmar Warehouse in London,” he concludes. “It’s an old play but still completely relevant. I’m really having a ball at the moment.”

Dublin Oldschool hits Netflix on June 1.