We’ve known for a while now that King’s Speech director Tom Hooper as his Les Miserables team plumped for a different approach to movie musicals. But though the idea of gathering a cast and having them sing their performance live on each take certainly provides for a better acting experience, it’s still not as easy as it looks. The new featurette, above, explains the idea.

Hugh Jackman, Anne Hathaway, Russell Crowe, Amanda Seyfried and Eddie Redmayne are interviewed about the process, and all seem to sing – pun entirely intended – its praises, talking about how they can alter their performance each time and not feel locked into choices they had to make in a studio months ago when the tracks were recorded.

Les Miserables’ cast also includes Helena Bonham Carter, Sacha Baron Cohen, Samantha Banks and Aaron Tveit. The movie itself will warble into cinemas on January 11.