It's the fundamental conceit of Tom Hooper's "Les Miserables": Rather than have his actors record their songs in a studio and then lip-sync when cameras were rolling later, he filmed his cast, which includes Hugh Jackman and Oscar front-runner Anne Hathaway, performing their songs live on set.
But the very conceit of the movie also proved to be one of the production's biggest challenges, Hooper said.
In this clip from the Envelope Directors Roundtable moderated by the Times' John Horn, Hooper and five fellow top directors -- Ang Lee ("The Life of PI'), Ben Affleck ("Argo"), Sacha Gervasi ("Hitchcock"), David O. Russell ("Silver Linings Playbook") and Kathryn Bigelow ("Zero Dark Thirty") -- were asked about filmmaking decisions they made that they might have regretted.
Hooper said that by filming his actors' singing live, the tempo would vary from take to take, making the work of his editors that much more difficult because you "can't necessarily intercut one take with the other."
Hooper said that while live performances were "a little bit of a nightmare," he didn't wish he'd made the movie any other way.
The full video of his remarks can be seen above.