What "Who Framed Roger Rabbit?" did for animated characters, Todd Berger hopes "The Happytime Murders" will do for puppets -- namely, take them off of the exclusive radar of children, and into adult storytelling.

As the screenwriter told CraveOnline, "I want to try and make the 'Heat' of puppets."

The in-progress film is a dark comedy that takes place in a world where puppets and humans live side-by-side, and it's expected to garner an R-rating when it is released in 2013. But while the puppets may look a little familiar -- Jim Henson's son Brian Henson is directing Berger's script -- don't call them Muppets.

"(I)t's not associated with The Muppets, which are owned by Disney. It's a movie in which puppets and humans co-exist and a lot of the supporting characters are all puppets," said Berger. "There's a whole cast of characters in the script that they're going to create from scratch.

Plot summaries at GeekTyrant.com and IMDbPro.com describe the film as a murder mystery in which the cast of a 1980s kid's show's start to get offed one by one. "A disgraced LAPD detective-turned-private-eye puppet -- with a drinking problem, no less -- takes the case with his former human partner," noted GeekTyrant.

And in case the R-rating won't make it clear enough, Berger says there will be plenty of activity not usually associated with puppets: "There is swearing, there's sex, violence, murder," he said. "Maybe with some work it could be PG-13, but as of now we've embraced the R rating."

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