Yahoo! TV Q&A: Josh Dallas previews the return of Jorge Garcia to 'Once Upon a Time'

"Once Upon a Time" is about to get supersized!

No, Sunday's new episode won't be longer than usual, but it will feature the return of a very large character -- Anton the giant, played by Jorge Garcia. He makes his way from Fairy Tale Land to Storybrooke to cause big trouble for its residents.

"[The episodes] keep getting bigger and bigger and bigger," star Josh Dallas told Yahoo! TV. "There are more twists and turns" coming in the next few weeks, he promised.

And Anton isn't the only mischief-maker in town. Cora's still up to no good; Hook continues seeking vengeance on Rumplestiltskin; and outsider Greg is starting to ask questions.

Read what Dallas told us about Anton's arrival, Greg's agenda, and the future of Prince Charming and Snow White's relationship.

The last episode featured the arrival of this mysterious stranger, Greg Mendell. Will he be causing trouble in town?

Greg is someone who's very interesting to everyone ... and someone that [David's] keeping his eye on. On Sunday's episode, we'll see him question Belle on what she actually saw. So, it will be revealed as the season goes on who this mysterious stranger might be.

There was a bit of conflict between David and Emma over their different approaches to being sheriff. Are they going to disagree again in the future?

Kind of like any father-and daughter -- or any kind of parent-and-child relationship -- there's going to be disagreements. Of course, it's added to the fact that they're both the same age, which is a difficult hurdle to come across. They, in some ways, have different ideas, and both are valid. Both come from different worlds, so I think they have a certain amount to learn from each other.

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David's also at odds with Mary Margaret on returning to Fairy Tale Land. Is that something that will continue to come up down the road?

I think that's going to be an ongoing theme certainly throughout the next few episodes -- about what their place is and where they belong and how their relationship can move forward in this new capacity, in this new environment where they find themselves.

You know, David wants to go home. He wants his family back, he wants his kingdom back, he wants his world back, because in a sense, that's his core, that's where he belongs. And David, being the eternal optimist, feels that he can go back and rebuild it and make Fairy Tale Land what it once was.

At the end of this Sunday's episode, something happens -- I don't want to give it away -- there's a scene where something occurs where it does give David a little bit of hope, the possibility of being able to go back.

Jorge Garcia returns as Anton, and it seems he has a grudge against David!

Cora, being Cora, has found an ingenious way of transporting a giant on a pirate ship. And David, upon meeting Anton on the pirate ship, is met with a violent hello. Of course, Anton mistakes him for someone else and holds a massive grudge toward this person, whoever it may be.

Watch a preview of Sunday's episode with Jorge Garcia as Anton the Giant:

So David's quest in Storybrooke is to figure out who he's after, who Anton thinks David is, and then try to convince him he's not this person. Meanwhile, Anton is wreaking his vengeance and his havoc on the entire town. So David, being a hero and a leader, has to step up to convince him that Storybrooke is not a bad place and the townspeople aren't trying to hurt him. And it's a place where maybe he can feel safe forever, who knows?

We also go back into Fairy Tale Land past, where we see Anton in Giant Land living with his brothers, feeling like he's out of place, like he doesn't belong, and that he needs to go in search of a place where he feel like he fits in. So, against his brothers' wishes, he climbs down that beanstalk and goes into the world of humans, where he meets a couple of humans who aren't exactly what they seem and whose intentions toward Anton aren't wholly noble. And maybe that's the origin of this grudge that he holds.

Is it possible that this person David is mistaken for is his twin brother, James? They do look alike, after all.

Oh, it's possible. Very possible. Of course, back in Storybrooke, David has a very good idea of who might know who Anton thinks David is, so he goes and finds that out. You will find out in this episode what David's/Charming's real name is.

What else can we expect from the next few episodes?

They just keep pushing the story, they keep getting bigger and bigger and bigger. There are more twists and turns. We're going to keep discovering who Greg is. We're still following Mr. Gold's quest to find his son, Bae. In this episode, he attempts to depart Storybrooke, and he's hoping his memory stays intact when he crosses the town line. And he's heading to the airport with Emma and Henry, and he's in search of his son. We'll see if he finds him and, if he does, what that encounter is like.

Watch a sneak peek from Sunday's episode:

We'll be figuring out Mary Margaret and David's relationship, and where they fit into the world, and how their hopes and dreams are met. They have a curse, in a way, that they are heroes and leaders, so they are always going to be called upon to help out others, so their hopes and dreams are kind of pushed aside for a little while.

"Once Upon a Time" airs Sundays at 8 PM on ABC.