George Clooney on tackling stolen Nazi art in The Monuments Men
12 February 2014 Last updated at 14:32 GMT
During World War Two a small group of men managed to get behind enemy lines and retrieve artwork which had been stolen by the Nazis.
George Clooney was so inspired by the story that he decided to make a film about it.
He spoke to the BBC's Will Gompertz in the conservation room at the National Gallery about writing, producing, directing and starring in The Monuments Men - and how he copes with bad reviews.