Beneath the spectacular square are little-known underground passageways called the "Deadhouse", which this week open to the public for the first exhibition of paintings ever to be held there.

Somerset House's resident artist Paul Benney is exhibiting his paintings in a free show running from October 4 to December 9, and in the dingy subterranean chambers they hang alongside the headstones of French courtiers buried there in the 17th century.

"This was a space that I had come across by accident as I was wandering about finding my way around and getting used to the building," Benney told Reuters in a dark vault surrounded by his works.

Traditionally, he would have held the exhibition above ground in a naturally lit gallery running along one of the four sides of the courtyard.

"It gave me the idea that ... this might be a better place to try to see whether it would work for my work, and as it turns out I think it does."

Benney, who has had a studio at Somerset House for 2-1/2 years, has produced a series of eerie, elemental images including a Pan figure floating above a forest, a naked man "emerging" from thick fog and a face whose shaved head has burst into flames.

"I don't set out to make eerie or unsettling work," said the artist, also a well-known portrait painter. "It does eventually come across as that, I think, as a coincidence, as a result of me finding imagery that makes sense to me.

"My influences range from 20th century cinema like (Russian director Andrei) Tarkovsky right through to Rembrandt and Goya. Generally, of all those artists I am drawn to the subterranean subject matter."

That includes Goya's "Black Paintings", the Spanish artist's haunting canvases that include Saturn devouring his son and two ghoulish old men eating soup.

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As well as the Deadhouse, a handful of Benney's works hang inside alcoves along the "lightwells", deep, paved alleyways that run along three sides of the court above.

Officials at Somerset House are hoping the combination of an innovative space unknown to most visitors and the art on display will make the "Night Paintings" show a major draw.

The Deadhouse has been used before as a party venue and for a sound installation, but damp conditions, and the fact that it is a service tunnel used by the venue, limit its potential as a permanent art space.

Somerset House Trust was set up in 1997 to conserve and develop the site and open it up to the public.

"We were only set up 15 years ago and opened to public in 2000, and we have been investigating how to show different parts of the building to the public," said trust director Gwyn Miles.

"We have used (the Deadhouse) for events - we've had some fabulous parties down there and we will use it probably more."

The headstones were set in the walls of the tunnel when Somerset House was rebuilt by William Chambers at the end of the 18th century.

When the old buildings were demolished to make way for the buildings that survive today, the graves of members of the queen's court were disturbed.

The headstones date back to 1637, when Henrietta Maria of France, who married Charles I, used what was then called Denmark House and had a Roman Catholic chapel built - a deeply unpopular move at the time.

Henrietta fled to France during the English Civil War in which her husband Charles I was executed, but returned to Denmark House as Dowager Queen after the restoration of Charles II in 1660, and launched a new phase of expansion.

(Reporting by Mike Collett-White, editing by Paul Casciato)

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