Alex Hirsch doesn't have to look far when coming up with story lines for his Disney Channel series, Gravity Falls.
The creator/executive producer of the animated series had himself and his sister in mind when he created the two main characters -- 12-year-old twins Dipper (voiced by Jason Ritter) and Mabel (Kristen Schaal), whospend summer with their eccentric great uncle Stan (voiced by Hirsch) in the wondrous town of Gravity Falls.
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"I tried to create a show about the summers that me and my sister spent, but what if they were crazy?" Hirsch told The Hollywood Reporter at Disney's recent D23 Expo in Anaheim, where they were signing autographs for fans at the Disney Channel Pavilion. "What if instead of roasting marshmallows and going on kayaking trips, we got to punch pterodactyls in the face and fight a thousand gnomes and travel back in time?"
The show has struck a chord not only with kids but also adults. Many over-18 attendees at the D23 Expo were carrying oversize bags adorned with the show's iconic rainbow-vomiting gnome, which were for sale at the event.
"I think the success of the show comes from the balance between the grounded actual family dynamic and the fantastical," Hirsch said.
For her part, Schaal -- who hasn't actually met Hirsch's sister due to location differences -- said she thinks the appeal is that "it's a smart show."
And, she added, the audience "knows it's a smart show and they are up for the challenge in this special club they belong to."
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Last month, Disney Channel announced that it had renewed the series for a second season. So what's next for the twins?
"Lots of fun, lots of adventure, mystery, intrigue, laughs and touching moments," Schaal said.
Added Hirsch: "All the dynamics of season one with the comedy, mystery and action will be back, but we'll have bigger, scarier monsters. Mabel will have weirder sweaters than you've ever seen before. Our characters are definitely in a position where they're dealing with higher stakes than ever seen before."
Asked if Hirsch's sister actually wore such sweaters growing up, he replied that she did, in fact, inspire the character's wardrobe thanks to a "lime green troll doll" sweater she once wore to school.
Does she ever get upset about how she's portrayed in the series?
"She's since calmed down a bit, but it's all based on fact," he quips. "I've got plenty of family weirdness left for season two."