For many years I had a thing about Trainspotting – it annoyed me, but not for the reasons you might expect.

Its graphic heroin scenes, lurid squalor and euphoric nihilism turned a grim tale about Edinburgh’s drugs epidemic into a cinematic classic, not to mention a 90s pop culture icon. And the soundtrack is superb. I get it.

So what was it that bothered me? The truth – they chose a posh lad for the lead role. Now this is not a personal attack on Ewan McGregor, honest. And I don’t feel that way now. He is a fine actor and he did a fantastic job.

But as with so many actors in the profession today, having a privately educated, middle-class background has equipped the Benedicts, Eddies, Tildas, Emilys and Olivias with an instinctive understanding of the values needed to mix and thrive within the metropolitan arts set, as well as the language tricks, financial safety net and the confidence to pull it off. It also helps if you have family connections.

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Just seven per cent of the UK population are educated privately, while, according to a 2016 study by the London School of Economics and Goldsmiths, University of London, 73% of performers are described as middle class.

So bravo to Line of Duty star Vicky McClure and her fiancé, Jonny Owen, for launching their production company, BYO [Build Your Own] Films, with its mission statement to give those from less privileged homes an opportunity, and, where possible, hiring local writers, cast and crew.

McClure, the daughter of a joiner and a hairdresser, knows the pain of having a dream crushed, having had to turn down a place at a top London acting school because her parents couldn’t afford the fees. It makes her success all the more remarkable.

Do I sound as if I have a large working-class chip on my shoulder about this? I admit it, I probably do. Years ago I dabbled in amateur dramatics and, sure, there were lots of wobbly sets and fake twirled moustaches, but it was also serious stuff. To perform in front of a paying audience, a certain level of “professionalism” was expected.

Mess up on stage and you knew about it, and more importantly, so did those watching. Putting on a show costs money, and it’s bums on seats that pay the bills. Trust and teamwork are everything, and, of course, talent helps. I met many people who were brilliant, and could have gone on to bigger and better things, had circumstances allowed.

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Indeed, I even harboured hopes of pursuing a career in the industry myself. However, when the dates came round for my auditions in London, my bottle crashed and reality kicked me in the teeth. I could neither afford it nor had the support network.

If I’m honest, I’d never have got through even if I had gone for it – having watched a video of myself attempting a Yorkshire accent in Billy Liar at the 1999 Edinburgh Festival, I’m amazed there wasn’t a stampede for the exit doors.

But those with talent must be allowed to rise to the top without the risk of being strangled by an old school tie. It can and does happen despite the overwhelming odds – just look at Alan Cumming, Kelly Macdonald, Brian Cox and let’s not forget Big Tam and the Big Yin. But they’re exceptions to the rule.

Indeed, McClure’s excellent co-star Martin Compston could easily have been lost to us had he not been plucked out of obscurity by Ken Loach all those years ago. He shines with the brightest of stars. If only it happened more often. Now we’re sucking diesel.

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