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Ever wondered how Robin Hood became the famed merry thief?

will finally delve into Robin Hood’s (Sean Maguire) backstory during Sunday’s episode, which also takes a look at how the prince of thieves has been dealing with living in the real world. The honorable archer left Storybrooke when his late wife, Marian (Christie Laing), who was brought back from the past, was stricken with a fatal bout of frostbite. How is Robin dealing with having to leave his new love Regina (Lana Parrilla) behind? EW caught up with Maguire to find out:

ENTERTAINMENT WEEKLY: What can you tell us about the Robin Hood flashback episode?

SEAN MAGUIRE: We’re going to find out a little bit about how he became Robin Hood, essentially. We’re going to find out why he chose the lifestyle that he did.

In the past, Rumplestiltskin (Robert Carlyle) enlists Robin to steal something from the Land of Oz. What can you tease of facing off with the Wicked Witch (Rebecca Mader)?

He’s basically put in a very difficult position because that’s what Rumpelstiltskin does. Because Robin Hood appeared in a different incarnation earlier, when Tom Ellis played the role, we touch on that a little bit. There’s a lot of, “Oh, so

.” There’s a few moments of that in the episode, without giving too much away. It’s really cool. It’s juxtaposed between the modern and the flashback and they tie in quite seamlessly.

Some photos leaked online that included Robin Hood and the Wicked Witch in Storybrooke. Is there anything you can say why we’re seeing them back in town since we all had assumed the Wicked Witch was dead and Robin Hood couldn’t return to town?

I can’t talk about that, but it picks up where Robin had left off once he left with Marian. Obviously, they’re in New York now. Robin does a bit of soul searching while he’s away. He obviously misses Regina enormously. It’s him trying to figure out how to do the right thing. He has to reconcile the fact that he’s still very much in love with Regina. It’s that thing between trying to be honorable, but trying to be decent, but also trying to follow your heart. He’s in a very tough situation in this episode.

How does his feelings for Regina affect his relationship with Marian?

That’s pretty much the crux of the episode. Robin said he made his decision, he’s in love with Regina, but Marian had a second attack from the Frozen thing, so he has to do what’s right as opposed to what his heart tells him. He’s trying to figure out what’s best to do. It’s also interesting to explore the dynamic with Robin, Roland and Marian because it’s his wife and he did once love her. How does he acclimate himself to getting back into a relationship that he had given up on? It’s a bit like the first love of your life comes back into your life just when you started to settle down with somebody else. How does that spin one out and confuse things? It’s difficult because your heart can’t unlove somebody.

In the last episode, Rumple said he has plans to essentially blackmail Regina into helping him. How would Robin Hood feel if Regina went evil again?

Robin Hood has fallen in love with a person he sees a lot of himself in. He’s had a long journey to get where he’s got and become the man that he’s become. He sees a lot of that in Regina, somebody with a shady past. They’re kindred spirits. It’s a real Romeo and Juliet thing. He fell in love with her from the start and Regina grew to love Robin. Once something like that starts, you just can’t turn it off. It’s going to be a moral quandary for how he deals with this. The episode, because it goes back into the past, we also get to see the start of another friendship with Will Scarlet (Michael Socha) as well.

The relationship between Robin and Will seems to be like big brother and younger brother. We see the genesis of that. In the spinoff show,

, we saw what I thought was probably their first meeting, but it turns out there was a meeting before that, which is why Will was allowed to become one of the Merry Men later on down the line. It’s a prequel episode juxtaposed with what’s happening right now.

What kind of interaction will Robin Hood have with the Sheriff of Nottingham?

That’s what gets the ball rolling. You’ll see that he does make an appearance and he’s one of the reasons why Robin has to go and do what he does in this episode.

Will we see Robin Hood have any interaction—in this episode or the future—with the Author (Patrick Fischler)?

He may do. The Author is going to affect everybody to some degree. Patrick has scenes with almost all of us.

Ultimately, do you think Robin Hood and Regina are meant to be?

As a fan of the show, yes, completely. I just think that’s the way it’s been written. If I was just sitting and watching the show, I would be into Robin Hood and Regina. At the same time, he’s got to do the right thing, so it’s going to be tricky.

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