Skeptics scoffed when “How to Train Your Dragon” opened to a fraction of what previous DreamWorks Animation features had earned on their first weekend, then watched in awe as the animated feature prevailed, buoyed by word of mouth and great reviews to become the studio’s top non-“Shrek” domestic release.

Grossing $493 million worldwide to date, “Dragon” was shepherded to the screen by a sole producer, Bonnie Arnold, whose previous animation credits include DWA’s “Over the Hedge,” Disney’s “Tarzan” and Pixar’s “Toy Story” — toons that have collectively earned more than $1 billion worldwide.

Arnold credits much of her success to DWA honcho Jeffrey Katzenberg, who called her into his office as “Hedge” was wrapping up and asked, “Have you thought about what you want to do next? You tell me what you want to do. You can do anything here.” Arnold instantly named “Dragon,” since she had just read — and loved — Cressida Cowell’s young adult novel, the first book in a fantasy series that the studio’s development team was planning to option. Katzenberg agreed, promising, “We’ll wait for you.”

The studio accommodated her even further, allowing Arnold to produce her live-action passion project, late-life Leo Tolstoy romancer “The Last Station,” at the same time. “My first priority had to be to DreamWorks,” says Arnold, who insists the studio was “very understanding” regarding the indie production.

An Atlanta native, Arnold began her film career in live action, working as a non-union production coordinator and location manager in Georgia. After moving to Hollywood, she served as an assistant on “Revenge,” where she met up-and-coming star Kevin Costner (later earning her first associate producer credit on “Dances With Wolves”).

But animation was where Arnold found her niche, discovering a specialized field where she could practice all her skills. Referring to her role at DreamWorks, where Arnold is beginning development on the “Dragon” sequel, she says, “The producing job here is much more like the studios in the ’30s and ’40s, where the producer has a creative role to play, as well as managing the money and schedule, working with the marketing folks — you’re involved in every aspect of the film.”