Antiques Roadshow expert Frances Christie branded a find “one of the best I’ve seen” in a classic episode set to air again on Sunday.

The episode, which came from Pollok Country Park in Glasgow, saw art specialist Christie valuing a “really exciting” painting which had been purchased for just £5.

“Now this is a really exciting picture to find on Antiques Roadshow, because it’s by an artist who grew up around here, Dorothy Steel, who really should be so much more well-known than she is,” she explained before asking the couple who own the painting where they’d found it.

“I found it in a charity shop, in a place not far from here about 20 years ago,” one of the guests replied.

He added: “And I could see straight away it was a quality painting, certainly worth the £5 they charged me for it.”

“What else drew you to it?” the art expert probed, to which he responded: “Well, it’s a typical west of Scotland scene there, you can see the docks, the shipyard cranes in the background. It’s the back of a tenement.

“I’m guessing it’s either Port Glasgow or Greenock, where Dorothy Steel was from.

“And it just appealed to me, the colours, it’s got the impressionist softness and the light – the subject matter most of all.”

“And it just has that mid-century look, which is just really nice,” the other guest added.

She went on: “And [it has] a nice kind of flatness, I think, about the painting as well that’s really attractive.”

“I mean, she went to the Glasgow School of Art,” Christie revealed, adding: “And you can tell she had this amazing facility with colour and light, and she was clearly drawn to the landscape that she grew up with.

“I mean, she lined in and around Glasgow her entire life. This totally shows off what Steel was really good at, and that was painting a scene that she would have seen day in, day out while she lived here.

“And actually, it’s a scene which has kind if disappeared now.

“I don’t know if these tenements are still there, but in terms of social history, going back to the middle of the last century when Steel was painting, it probably still would have been teeming with activity, whereas today it’s a very different part of the Clyde.”

After the guests reminded her they’d paid only £5 for the piece, one of them quipped: “I think we probably paid more for the taxi to take it home, because it was raining that day.”

“In my opinion, this is probably one of the best Steels I’ve ever seen,” Christie enthused.

She continued: “Her work doesn’t come up at auction very often at all, but I think if this were to come to auction today, I would put an auction estimate in the region of £3,000 to £5,000.”

“Oh my goodness,” the woman responded before the gentleman added: “Oh, nice. Wow.”

He later joked: “I can’t think of any better fivers that I’ve spent. I can’t imagine getting more value for money, that’s for sure.”

Seeming to reveal their plan to hang onto the painting, the woman added: “I’m very pleased it’s worth a lot of money, but it’s worth a lot more than that to me.”