The painting used to hang in Bridgewater House in London, and was thought to have been destroyed by a bomb during the Second World War.

But in fact the picture had been evacuated to a country house on the Scottish borders. National Gallery staff were told, “We’ve something rolled up – come up and see it.”

The picture was unrolled for the first time this summer, and was covered with more than 200 cuts caused by shrapnel, which you’ll be able to see at the exhibition.

“For the first time in our history we are showing this picture only partly restored,” says curator Christopher Riopelle. “You will still see the shrapnel wounds.”

The show will also feature Delaroche’s The Execution of Lady Jane Grey, described by Riopelle as “the most famous and one of the most popular paintings in the National Gallery”.

The painting “created a sensation when it was shown at the Salon in Paris,” says Riopelle. “So lifelike was this picture seen to be in 1834, it attracted huge crowds.”

The crush led to the creation of the first-ever museum barrier.

Because of the vivid quality of Lady Jane Grey’s dress, the work will appeal to fashion fans. Vivienne Westwood, Alexander McQueen and Agent Provocateur have all been inspired by it.

Like the Charles I picture, The Execution of Lady Jane Grey was once thought to have been destroyed, after a flood at the Tate, where it was on show.

We’re looking forward to seeing, in Riopelle’s words, “two of Delaroche’s greatest paintings – both back from the grave”!

Delaroche and Lady Jane Grey is at the National Gallery from 24 February to 23 May 2010.