THE LATEST challenge facing Johnny McKnight, on the face of it, looked to be one of the toughest he’d encountered. And that’s including the comedy, Wendy Hoose, he once wrote about a dating app user whom we learn has no lower limbs.

How do you write a script featuring a great Glasgow 1920a story about the demi-monde of closeted gay men, in which the gay men are thugs - yet inject them with humanity and substance?

Meet Me at The Knob is a musical which tells the story of The Whitehats. These men were mostly homosexual vaudeville performers who dragged up at night on the city’s Broomielaw and preyed upon gay businessmen.

The powdered faces and painted nails soft image belied the fact that these male prostitutes made closeted businessmen’s life a living terror. The group, who used female pseudonyms, were led by William Paton, known as Liz.

Darren Brownlie, a River City favourite and now established as one of Scotland’s major panto stars, plays Liz. “This is a Glasgow gay version of Peaky Blinders,” he explains. “He’s a sort of Fagan character who has these boys working for him, their job being to sleep with magistrates or MPs and then blackmail them.”

The play takes us into a world of bleak despair, an era when to be gay was illegal. (It was 1980 before homosexuality was legalised in Scotland.) Gay men sought company where they could find it. But all too often, the company proved to be less than friendly.

Brownlie admits he found the role to be incredibly demanding. “I’m not going to lie, I found this really hard for me to play. I’m usually a goodie in theatre. Director Jemima Levick said to me I had to leave that part of me behind to get into the character.”

But no one is all bad, is that right? “I suppose that when you think of Liz, she’s not so much a baddie, she’s part of that world, even if she is a basically a gangster. Yet, I’ve never had to go into something like this which makes you reach so far into your own character, to see what you can come up with.” He adds with a laugh. “But we’re all actors. We do what we’re ‘telt.”

What Darren Brownlie, who is set to tour in a drag production of the Steamie, has to work with of course is McKnight’s razor-sharp script, a writer who seldom creates monochrome characters. “That’s the beauty of Johnny’s writing,” says the actor. “He’s great at writing comedy, and there’s comedy language in it, but this is also a really beautiful piece. And Johnny manages to capture that wee element of danger running all the way through it, but with so much heart to it.”

He adds, smiling; “If Johnny knows anything it’s how to take audiences down the rabbit hole. But I love the story. It’s fascinating to discover this world of darkness. And when you realise some of the boys were dancers or whatever at the Panopticon, who would go from their theatre work to earning money from bribery and extortion, it’s quite incredible. And we learn of this judge who is living a lie.”

Darren Brownlie says the musical works on so many levels; it’s a reminder that homophobia hasn’t really gone away. “You only have to look at America today. It feels like a circle, and the problems go round and round.

“You just have to look at the recent example in Dundee where a drag performer was banned from reading children’s stories. It’s worrying.”

The plays is also a reminder of how desperate people do desperate things. “This is a great historical piece that offers an insight into Glasgow in the Twenties. And if there’s a message, it’s that we should always be kind, because we’re never really sure of what’s going on in other people's lives.”

Darren Brownlie is joined on stage by Dylan Wood who plays Fanny, and Tom Urie plays Alan, the Judge.

Meet Me At The Knob, Oran Mor, Glasgow, until Saturday.