Tim Burton's Bloody Christmas

Dec. 18, 2007— -- Tim Burton's new movie may live up to one of the acclaimed filmmaker's past films and cause quite a few real-life nightmares before Christmas.

"Sweeney Todd: The Demon Barber of Fleet Street," a remake of Stephen Sondheim's Broadway musical about a murderous barber hell-bent on revenge, stars frequent Burton collaborators Johnny Depp and Helena Bonham Carter in roles many people have yet to see -- singers.

"It's like 'The Sound of Music," but with blood in it," Burton said as he stopped by ABC News Now's "Popcorn" to discuss the movie with Rolling Stone's Peter Travers.

New Songbirds

According to Burton, the "Sweeney Todd" stars lack of musical training gave the film an emotional quality unachievable by actors with a singing background.

"I realized after casting a few parts that none of [the actors cast] were professional singers, but when I heard them [sing] they brought something to it which I thought was really amazing," Burton said of Depp and Carter. "They brought an emotional quality to it. They couldn't rely on their singing ability, so something had to come from within."

Despite being the mother of Burton's two children, Carter had to go through a rigorous auditioning ordeal for her role as Mrs. Lovett, a pie maker who grinds up Todd's victims into meat pies. In the end, the filmmaker decided she was right for the role opposite Depp.

"Part of it is the image of those two together. They're such a weird couple, which was very important in the kind of visual quality of them," Burton said. "I always had this image of, because I used to love to go to wax museums, that if I could see those two figures in a wax museum, then that's the right image."

The Sound of Music

Having music on the set was also a liberating experience for stars like Depp.

"[Johnny] picking up a razor to music, he picks it up completely different to music than he would if he was to just walk over and pick up a razor. It was amazing to see actors acting sort of rhythmically in a way that I've never seen them act before," Burton said. "It also galvanizes everybody, the crew, everybody gets in the same zone. You see people, the grips, mouthing the words -- there's a unifying force to [the music] that's really amazing."

Please click here to read Peter Travers' Rolling Stone review of "Sweeney Todd."

Monster Movie

For those unfamiliar with the story of "Sweeney Todd," Burton likens the film to the black-and-white horror films of the past, but with a soundtrack.

"Its roots are just those old-fashioned horror movies and what's so strange is the music just seemed to fit right in even though they're almost two opposite things, but that's what gave [Sweeney Todd] it's unique quality," Burton said. "I never really thought of it just as a musical or as a horror movie. It just sort of made this new kind of thing, which is what struck me when I saw it onstage."

Broadway Baby

Burton, known for his dark films, was first attracted to the stage version of "Sweeney Todd" many years ago. He had little knowledge of the theater or talents like Sondheim, who is known for his work in showstoppers like "Gypsy," "West Side Story" and "A Funny Thing Happened on the Way to the Forum."

"When I first saw the show I was a student, and I wasn't a big theater-goer and … it just blew me away," Burton said.

The Academy Award-nominee (for 2005's "Corpse Bride") believes his inexperience with traditional theater allowed him more creativity when turning the musical hailed by many as Sondheim's best work into a movie.

"I loved the show but I didn't know much about [Sondheim] or musicals so I was a bit naive to it and I think that actually helped me to not feel so nervous about doing [the film version,]" Burton said.

And for all the Broadway faithful -- Sondheim did give the movie his blessing.

"[The show's] been around for so long that he understood it was a movie so he accepted the fact that things would change and we'd do things you wouldn't ordinarily do on stage," Burton said.

A Great Partnership

Johnny Depp has become a mainstay in Burton's movies. Staring with "Edward Scissorhands" in 1989, "Sweeney Todd" marks the duo's sixth collaboration.

"As soon as I met [Depp], I knew he was right for the role [of Edward Scissorhands]. I didn't know the guy at all but I just felt like he was in this show '21 Jump Street' and people were looking at him like a teen idol and you just got a sense that wasn't in his heart and soul and so for me he very much mirrored what the Scissorhands character was," Burton said.

That character has led to many memorable roles in Burton's movies.

"He's a character actor; he's not a leading man. I've worked with him six different times and he was like six different people," he said. "He doesn't like looking at himself. ... He just gets in there and inhabits a role and … it just energizes everybody."

You can catch Johnny Depp in "Sweeney Todd" in theaters starting Friday, Dec. 21. For Tim Burton's entire interview with Peter Travers, please tune into ABC News NOW.