Jennifer Morrison Jennifer Morrison

Since Once Upon a Time premiered, the big question has been whether Emma (Jennifer Morrison), the unwitting daughter of Prince Charming (Josh Dallas) and Snow White (Ginnifer Goodwin), would be able to rescue the trapped fairy tale characters of Storybrooke, Maine. The first step in that process, of course, has been the most difficult: getting her to believe that fairy tale characters are actually real.

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Needless to say, her doubt can only stand for so long. "There's definitely a drastic difference between the beginning of the season and where it ends," Morrison says. "People can count on there being a serious amount of growth for Emma."

A recent promo — in which Emma and the town appear to rebel against Regina (Lana Parrilla) — seems to indicate that Emma has finally gotten the hint. However, Morrison remains mum on whether the scene is real or a dream sequence. (We hope for the former!) "What we're seeing now is whether or not Emma is really going to accept her role as the savior," she says. "It's do-or-die at this point. The stakes are so high as we go through these last few episodes."

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For now, though, Emma appears to be on her way out of town, with Henry (Jared Gilmore) in tow. But she won't get very far. "[Henry] actually takes the wheel while she's driving and causes them to crash so they can't leave town, which obviously really freaks her out," Morrison says. "She's like, 'My God, you're actually willing to die over this! You're 10 years old — how can you be thinking this way?' Obviously, that's a big eye-opener for Emma. If this child is that extreme about it, she obviously needs to take a step back and figure out the best way to make sure she keeps him safe and does the best thing for him."

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Morrison says that the cliff-hanger will leave fans wondering what the show will even be like next season. "It's so massive and so game-changing," she says. "I mean that in the best way. I read the season finale and went, 'Oh my God! What is going to happen?!'" While Morrison notes that the core characters and brand of storytelling will remain intact, "thematically, there is going to be such a drastic shift that it will be a whole new adventure" in Season 2.

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Once Upon a Time airs Sundays at 8/7c on ABC.

(Additional reporting by Adam Bryant)