'The Boxtrolls' Trailer: They're So Square (Baby, Cee Lo Doesn't Care)

A world where clever, sneaky little trolls who wear cardboard boxes so they always have some place to hide is going to be a little weird. So the sound of R&B star Cee Lo Green singing a song made famous by Elvis Presley and Buddy Holly fits right in.

"The Boxtrolls" is an upcoming stop motion animation film from the same studio who created the visually stunning films "Coraline" and "ParaNorman." But while their previous movies got into some dark territory with ghosts, zombies, and witches who wanted to replace children's eyes with buttons, "The Boxtrolls" is more of a zany, fast-paced romp. And that's where Cee Lo comes in.

The song featured in the new trailer is "(You're So Square) Baby, I Don't Care," a 1957 composition by Jerry Lieber and Mike Stoller, the Rock and Roll Hall of Fame-inducted duo behind hits like "Hound Dog" and "Stand By Me." Elvis Presley recorded the song that year and performed it in the film "Jailhouse Rock." Buddy Holly released his cover of the song in 1958, and Cee Lo Green recorded his own amped up version 53 years later for the tribute album "Rave On Buddy Holly."

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In a phone interview with Yahoo Movies, director Anthony Stacchi told us the propulsive beat of Cee Lo's track matched the energy of the film. He said, "We had two previous trailers that were a little quieter, and we wanted one here that definitely emphasized the fun and the action/adventure part [of the film]." The fact that the words also reflected the geometry of their main characters' choice of apparel also made it the perfect fit. Stacchi said, "When we heard it and we heard the lyrics, it just totally made sense."

The movie is based on the book "Here Be Monsters!" by Alan Snow, a fantastical book for young readers about a lone boy making his way through (and under) his odd town of Ratbridge with the help of the shy but loveable Boxtrolls. Stacchi said the book's setting of a "steampunk, Victorian, Monty Python-world seemed perfect for the look of stop motion." He added, " You can’t ask for better characters to animate in stop motion than guys who live in magical boxes that pop in and out of the top of."

The process of stop motion animation is one of the most arduous and labor-intensive forms of filmmaking, since every character, setting, and prop has to be specially built and then delicately adjusted frame-by-frame to create movement. Co-director Graham Annable told us that their team spent six months just building the stop motion puppets before they could even begin shooting. Annable said the Boxtrolls' defining characteristic -- their ability to hide quickly and completely in their box -- was also the biggest challenge technically: "Their arms and legs have to be able to come out and go in separately at different speeds, and their heads need to disappear inside, and at the same time, they need to be capable of all the range of movement of any kind of a normal, human puppet."

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"The Boxtrolls" is the third stop motion feature from the animation studio Laika, and their previous two releases, "Coraline" and "ParaNorman," both earned Oscar nominations for Best Animated Movie. So the animation team pushed itself to top what they had accomplished before both in terms of scale and complexity. Stacchi revealed that their producer Travis Knight, who made the earlier films, rejected the original designs for the characters because they weren't challenging enough. Stacchi said that Knight "likes to be scared because he doesn’t know how we’re going to do it, and in a way, I think that’s what keeps it interesting for him and keeps the studio moving forward… We’re not doing something right if we’re too comfortable."

While the animators might have scared of how they would make the characters work, the directors did stress that the final product is not that scary for viewers. Stacchi said, "It's a very different beast from 'Coraline,' I feel, in the tone of it." And while the Boxtrolls might look a little odd from the outset, they quickly become endearing. Annable concluded, "When your average person sees a Boxtroll, they’re a little afraid of them at first… but the story tells you, never judge a book by its cover."

But maybe you can judge a song by the cover version.

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Featuring the voices of Ben Kingsley, Elle Fanning, Simon Pegg, Nick Frost, Toni Collette, Jared Harris and Tracy Morgan, "The Boxtrolls" opens on Sep. 26.