A lot of people believe 12 Years A Slave is the best film yet made about slavery in the United States. That doesn't make it easy to watch.
It also wasn't easy to edit.
"Editing is like a massive, 5,000-piece jigsaw puzzle," says director Steve McQueen. He's just arrived from Europe and is relaxing in a suite in a swanky West Hollywood hotel with the film's editor, Joe Walker.