Diane Parish, who plays Denise Fox, bought a limited edition of Niall Conlon’s piece More, which calls for more Irish, more blacks and more dogs.
Taking to Instagram, she praised the artist and said her parents had encountered prejudice after they moved to England from the Caribbean.
Diane’s endorsement came as Niall, a former Ulster Rugby player and city dealer who quit the worlds of sport and finance to concentrate on his art, launched his first solo exhibition at London’s Zari gallery.
One of the buyers was his childhood friend Jamie Dornan, who already has a number of his pieces on the walls of his home in England.
Niall, who is hoping to open an exhibition in Belfast, said More had been a game-changer for his career.
He added: “I decided to challenge the old racist messages that were once said to have been common in England, making it clear that people renting out property didn’t want to have anything to do with black or Irish people. There were also notices that ‘Irish need not apply’ for jobs.
“I’d heard some people in England trying to argue the anti-immigrant signs never actually existed, but I did some research which confirmed for me that they weren’t myths.
“I resolved to turn a negative into a positive in my painting, which caused quite a stir. It sold so quickly that I decided to make prints, and they have been bought all over the world including, I’m happy to say, by the Ulster Museum.
“The More painting, which is raw and in your face, seems to have been appreciated particularly within the Irish diaspora, who maybe remembered their grandparents telling them they had been faced with the signs back in the day.
“The fact that Diane bought one of them and publicly supported me was a massive boost. When it came to a follow-up exhibition I hit on the name More is More.”
Niall, who works from a studio on Belfast’s Lisburn Road, said many of his paintings featured what he calls “mad red dogs” which he knows people either love or hate but which help him “create edgy, visceral art that makes folk sit up and take notice”.
At a time of wars in Ukraine and the Middle East, the Zari gallery said Niall’s work was particularly important.
It added: “He invites us to reflect on the desire for harmony in a world marked by fierce, untamed forces.”
Niall said having the likes of Dornan in his corner had been a huge boost to his career.
He credits the actor with persuading him to take a risk, give up his job in London and go full tilt in the precarious world of painting.
“He has always been incredibly encouraging. As soon as I showed him some of my paintings, he wanted to buy them,” Niall explained.
“Last year he was extremely supportive of our art project designed to raise money for mental health charities.”
Niall and his fellow Belfast artist Paul Doran raised thousands of pounds for the Minding Minds Together project.
Jamie was present at a function to promote the charity and discuss the benefits arts and sports can have on mental health.