A BID by Netflix to fit a plaque marking a hit TV series at a historic Edinburgh landmark has been condemned by a heritage watchdog.

The streaming service initially installed a red plaque with a quote from One Day erected in The Vennel, where its lead characters have a key scene.

It has applied to City of Edinburgh Council, external for planning permission as the sign would be secured to the wall of a listed building, built in 1910.

(Image: Netflix) But Cockburn Association director Terry Levinthal called for planners to refuse permission, arguing it was a "simple exercise in product marketing".

One Day, based on the book by David Nicholls, follows the lives of Emma Morley and Dexter Mayhew on St Swinthin's Day – 15 July – every year.

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They meet at their Edinburgh University graduation ball in 1988 and have a failed one-night stand.

The series explores the couple's relationship as they grow up, move apart and together, and experience joy and heartbreak.

One memorable scene in Edinburgh was filmed in The Vennel, a historic staircase that runs from the Grassmarket along the boundary of George Heriot's School.

(Image: Andrew Abbott) At the top of the steps is a famous view of Edinburgh Castle.

The plaque was temporarily installed at the site on July 15 this year to mark the One Day date, but now plans have been submitted to make it permanent.

The sign commemorating One Day is proposed for the bottom of the stairs and on the opposite side to the 16th Century Flodden Wall - which once marked the perimeter of Edinburgh.

(Image: Netflix) The quote on the sign reads: "It's one of the great cosmic mysteries. How someone can go from being a total stranger to the most important person in your life."

Yet Levinthal said he felt strongly about the issue.

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He told the BBC: "Edinburgh is a very popular city for filmmakers world-wide.

"If every production or every connection with a novel or film or TV series did the same, one wouldn't be able to see parts of the city due to the proliferation of plaques.

"Is Netflix's One Day a hugely important cinematic masterpiece? No. Are the characters Emma and Dex that important for such commemoration? Again, the simple answer is no.

"Is this a simple exercise in product marketing? Yes."

He said the Netflix production "really had nothing to do with Edinburgh" and most existing plaques in the city either related to key historic figures who had an important impact or role to play in the city, or to particular events or places.

He said it opened up the wider discussion about film tourism in the city.

"People will travel long distances to stand in the spot of their favourite film characters and the causation impacts of that can be considerable," Levinthal said.

The City of Edinburgh Council’s planning department will now decide whether or not to approve the planning application by Netflix to allow the plaque to be installed permanently.

Netflix declined to comment.