While Pixar director John Lasseter was promoting “Cars” around the world in 2006, he began envisioning a sequel with sports-car star Lightning McQueen and tow truck Mater on the international Grand Prix circuit. Five years later, those familiar characters finally arrived on the world stage, and got snared in a spy caper to boot.

But “Cars 2” is just one of several 2011 toon releases that owe their existence to popular predecessors. DreamWorks delivered “Kung Fu Panda 2” and the “Shrek” spin-off “Puss in Boots,” while Walt Disney Animation released a new “Winnie the Pooh” in the classic handdrawn style. Beloved comicbook characters also got star turns this year, with Steven Spielberg and Peter Jackson transforming Belgian cartoonist Herge’s globe-trotting reporter into “The Adventures of Tintin,” while another Belgian comics property — Peyo’s blue-skinned, ankle-high Schtroumpfs — was animated by Sony in the CG/live-action hybrid “The Smurfs,” which was so successful that it’s already spawning a sequel. Clearly, franchise property values are staying high in this corner of Hollywood.

Despite the varied pedigrees of these pics, the challenge of taking an existing “brand” into a new movie remains the same: How do you do it without losing the spark that made those characters popular to begin with? “Cars 2” producer Denise Ream calls that aspect “the biggest challenge when you have beloved characters,” adding, “We had a spy movie, and it was a challenge to have an innocent character like Mater caught up in a conspiracy.”

To up the ante for “Cars 2,” Pixar did what many studios do with sequels: They “opened up” the picture by taking the characters to many European and Asian locales. Ream, who previously worked on big vfx films at ILM, says, “It’s one of the more complicated movies I’ve worked on. And it’s got the biggest scope of any Pixar film to date.”

DreamWorks also upped the action for “Kung Fu Panda 2,” adding a devilish foe for Po, the franchise’s pudgy action hero. Director Jennifer Yuh Nelson, story chief on the original, led a team of “Panda” writers and animators who moved directly onto the sequel. “It was almost a relief to keep going,” Yuh Nelson says. “Most of our crew was there when Po was conceived, so there was a sense of continuity. The nice thing about having established characters is that you can go for more subtlety and detail, and push everything further.” But Yuh Nelson cautions, “You can’t assert an unnatural story onto your characters. We would often say, ‘That’s not Po,’ and we’d make sure that wouldn’t happen.”

It’s typical for animated sequels to take characters forward, which is what happens to the dancing penguin star in Warners’ “Happy Feet Two.” Director George Miller advanced his story to present a “day in the life” of the original film’s penguin, who has become a father himself. By contrast, DreamWorks actually flashed backward to unveil the story of “Puss in Boots,” revealing how the sword-wielding kitty came to be the character auds met in the “Shrek” movies. “I always felt like he was a larger-than-life sidekick who could support a feature film,” says director Chris Miller, who helmed “Shrek the Third.” “Puss” is connected to the fairy-tale universe of “Shrek,” but in a style that Miller calls, “a mash-up.” As he says, “It was important that our fairy-tale characters (which include Humpty Dumpty and Jack & Jill) felt different compared to Shrek’s world. We created a mythology around them and had fun with them that way.”

Miller acknowledges, however, “It was pivotal to be surrounded by people who had worked on the ‘Shrek’ films and were aware of what they felt like. We always strived to make sure that this film felt different.”

A different task awaited the writer-director team of Don Hall and Stephen Anderson on “Winnie the Pooh.” They wanted to honor both A.A. Milne’s original books and Disney’s featurettes from decades ago. “They were the high-water mark of the franchise,” Hall says. Fortunately, the crew had animator Burny Mattinson on board, a veteran of those earlier short adventures. “He became our Pooh guru, and he encouraged us to really push it.”

One thing that definitely didn’t change in this “Pooh” was the British nature of the voice cast, which Hall felt tied the movie to its literary roots. “Winnie’s voice was untouchable. If we’d tried to ‘update’ him with George Clooney’s voice, people would be up in arms!”

Adapting characters from books to the screen can be a lengthy process. Spielberg has said he’s wanted to make “Tintin” since the 1980s, around the same time that producer Jordan Kerner first read “The Smurfs” books by Pierre “Peyo” Culliford. Since 1997, Kerner has worked to persuade the late author’s children that a big live-action/CG hybrid could do justice to Peyo’s stories. “They worked on levels for kids, but also dealt with more sophisticated behavior,” says Kerner, who also produced the hybrid “Charlotte’s Web.” “We felt that to create a world that the Smurfs can credibly live in, everything around them had to be real. If the human actors were too broad, the less real the Smurfs became.”

The “Smurfs” sequel, due in summer 2013, will take the characters from Gotham to Paris. “You toe a fine line when making movies for the world market today,” says Kerner, who admits that making toons come alive in movies remains a huge challenge. “It’s always a huge bar to get over.”

Animated pics boost property values
Whether working on a shoestring hand-drawn project or pushing the limits of computer-generated technology, this year’s offerings overcame major challenges in bringing their animated visions to screen. Here’s how:
‘Arthur Christmas’ | ‘Chico and Rita’ | ‘Gnomeo and Juliet’ | ‘Rango’ | ‘Wrinkles’ | ‘Rio’