A painting by the artist Francis Bacon will go on display for the first time in 25 years on Saturday after being found in a vault in Tehran, where it was mothballed following the Islamic Revolution.
The painting, Reclining Man with Sculpture 1960-1961,was bought by the Shah of Iran in the mid-1970s and hung in the Tehran Museum of Contemporary Art.
But when he deposed in 1979, the state took possession of it and stored it in the museum vaults. Like many pieces of Western art in Iran, it has not been seen since.
The painting came to light almost by accident.
Andrea Rose, an art expert from the British Council, was in Tehran sifting through the museum's collection in search of pieces to borrow for an exhibition.
She spotted the canvas and helped bring it to Britain, where it will go on display in Edinburgh this weekend as part of a major exhibition of Bacon portraits.
"I came across this painting I'd never seen before. It doesn't appear in any exhibition catalogues," Rose recalled. "It has been well kept and was in perfectly good condition."
The dark, disturbing painting shows a man draped on a black sofa, wearing a partially unbuttoned white shirt and with his left arm twisted behind his neck. In front of him is a coffee table on which stands a sculpture of a man's head.
Bacon hardly embodied the ideals of the Islamic Revolution.
A legendary gambler and drinker, he had several turbulent homosexual relationships during a Bohemian life which took him from his birthplace in Dublin to London, Paris, Berlin and finally Madrid, where he died in 1992 aged 82.
Best known for his tortured, expressionist paintings of distorted human forms, he painted several nudes.
"The museum in Tehran does have another Bacon which is a triptych showing two men in bed together. Obviously they could never show that in Iran after the revolution," said Ms Rose, the British Council's Director of Visual Arts.
She said, however, that Iranian authorities appeared to have taken good care of their Western artworks, whatever their subject matter, and were increasingly willing to loan them to museums and galleries abroad.
"They recognise that these works are valuable tools of international trade," she said.
Reclining Man with Sculpturewill hang in Edinburgh until September when it will be loaned to a gallery in Germany. It will then go back to Iran, where it is expected to be put back in its vault.