Jennifer Morrison Jennifer Morrison

We've seen Once Upon a Time travel to many lands, both magical and real world, but this Sunday the ABC fairy tale drama will venture somewhere it's never gone before: Into Emma's past!

This week's Once will travel back to when Emma (Jennifer Morrison) was vulnerable and wide-eyed, attempting to make it on her own as an adult for the first time. "You really get to see the difference of where she was at 10 years ago as opposed to now," Morrison tells, explaining that at 18, though damaged, Emma still had hope that life could change after being raised in the foster care system. "By the time we meet her on her 28th birthday in the pilot of Once, she doesn't really have as much hope that things can change. She's a little more resigned to the fact that life is always going to be hard and lonely. This show is her journey of rediscovering some of that hope, I think."

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Having lived most of her life on her own, Emma feels invincible at that age, making her way as a common thief to survive. "She feels like she survived so much already by 18," Morrison says. "You get to see the difference between someone at 18 under those circumstances and then 28 when, at that point, she's spent time in prison, she's had a child she didn't expect. Life has hit her on a whole other level in those next 10 years."

During Once's trip to her past, we'll meet a fellow thief who wants to make an honest woman out of her. It turns out, said thief is Neal Cassady (Michael Raymond-James), the mystery man we saw in the Season 2 premiere outside of Storybrooke.  "They were definitely kindred spirits," Morrison says. "There was a reason that she was so drawn to him and him to her. They had to survive to make life OK. There's an interesting parallel for them that they both are on their own in this world and have had to find inventive ways to make life OK."

Running parallel to her past on Sunday is the present story line of her journey up the beanstalk with Captain Hook (Colin O'Donoghue), both of whom are in search of a magical compass that may lead the way back to Storybrooke. "Captain Hook coming into her life now is a reminder of some of those things in her past," Morrison says. "She obviously is very distrusting of anyone she comes across in fairy tale land at this point because Cora [Barbara Hershey] has shape-shifted and all these crazy things have happened."

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Once the duo makes it up the beanstalk, they'll come face to face with the Jack and the Beanstalk giant, played by Lost and Alcatraz alum Jorge Garcia. "I think this giant is much quicker and angrier," Garcia says, noting that this is not like the Mickey and the Beanstalk giant, his only reference, who was dense and slow. (And don't expect to hear him declare, "Fee-fi-fo-fum.") "They go up there, and I'm what's up there waiting for them and I don't take kindly to intruders, so I'm definitely not happy that they're there and I give them some hell."

Whether or not Emma and Hook succeed in stealing the magical compass, we will likely see the giant again since Garcia has already been contacted to return. "There's definitely going to be at least one other story that's going to have the giant in it," Garcia said. "I think it would be cool to see what the giant is like in the Storybrooke world."

Are you excited to see Emma's past? Do you think Neal could be Henry's father? Hit the comments with your thoughts!

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