Judy Garland; Ginnifer Goodwin

Once Upon a Time has taken viewers to fairy tale land and Wonderland — and apparently, they'll even venture to Neverland next season. But what about the Land of Oz? It turns out that producers have hinted at a possible trip to The Wizard of Oz locale since the beginning.

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"What's interesting is if you go back and look at the pilot, there's a page of flying monkeys in Henry's book," executive producer Edward Kitsis says. "If I would go back and re-watch it — or buy the DVD coming out in August — and you pause on the book, you might see it."

The scene in question is when Emma crashes her car and the book goes flying. "The book flips through a number of pages. There are glimpses of images, one of which are the flying monkeys from Oz," executive producer Adam Horowitz adds. (Kitsis also notes that another blink-and-you'll-miss-it image from the pilot was that of the hookah-smoking Caterpillar, which was voiced by Roger Daltrey in the Alice in Wonderland-themed episode, "Hat Trick.")

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That same episode featured the Mad Hatter (Sebastian Stan) taking the Evil Queen (Lana Parrilla) through a portal into a room full of doors, one of which leads to Wonderland. "There are many different doors and I might've seen a green curtain," Kitsis says coyly, referring to the Wizard of Oz (played by Frank Morgan in the 1939 film) hiding behind a green curtain to mask his true identity. (Check out screen grab of the Oz symbol on the curtain here.)

"As we said in the episode with Wonderland, the Mad Hatter talks about all these worlds," Horowitz adds. "We're very excited about the possibilities for where we could show."

There are no current plans to venture to Oz in Season 2, but the producers are leaving the door open, an ABC rep said.

Do you want to see the Land of Oz on Once?

Once Upon a Time returns Sundays this fall on ABC.

(Additional reporting by Kate Stanhope)