The entire cast of the film were in attendance, with Hugh Jackman, Anne Hathaway, Russell Crowe, Amanda Seyfried, Eddie Redmayne, Samantha Barks and director Tom Hooper all walking the red carpet.
Digital Spy caught up with several key players including Jackman, Hathaway and Seyfried, to discuss the unusual decision to record all of the film's songs live on set, with no dubbing or ADR used afterwards.
"Particularly with this material, it's so emotional and so immediate," Jackman said, "so the idea of trying to dub something, or mime to something you did months before would have been probably harder.
"It was difficult, I won't lie to you, and I'm sure there's some takes I'm glad are not in the movie. But ultimately it was very freeing, and it meant we could be spontaneous."
Copyright: PA Images Ian West/PA WireSamantha Barks, who played the role of the lovelorn Eponine on stage in the West End prior to shooting the film, explained that Hooper's approach allowed the cast to experience the best of both worlds.
"When you're on stage, you have that live buzz, and there's nothing like that connection you have with the audience," she said.
"But the thing with screen is you can be so real, and so intimate, so singing this live on set really combined [those two]."
> 'Les Misérables' world premiere: Anne Hathaway, Hugh Jackman in London
> 'Les Misérables': Five new preview clips revealed - video
Les Misérables will be released on December 25 in the US, and January 11, 2013 in the UK.
Watch a clip of Jackman as Jean Valjean below: