Prepare for a double dose of doppelgangers on Sunday’s (Oct. 12) episode of “Once Upon a Time”

As Regina (Lana Parrilla) and Jekyll (Hank Harris) try to find a way to do away with their dark doppelgangers, the Evil Queen (Parrilla) and Hyde (Sam Witwer) make it their mission to stay alive and defeat their better halves. Meanwhile, Emma (Jennifer Morrison) and Hook (Colin O’Donoghue) prepare to move in together, while Snow (Ginnifer Goodwin) gears up for her first day back at school as a teacher.

Screener spoke with Parrilla about how it’s been to play both Regina and the Evil Queen this year — sometimes even at the same time — and whether or not she thinks either of them could be the hooded figure Emma saw in her vision of the future.

RELATED: He’s back! Sean Maguire’s Robin Hood returning to ‘OUAT’

It’s been so fun to see Regina vs. the Evil Queen this year. How has it been essentially acting against yourself?

It’s been really cool. It’s been quite the learning experience. I’d done some research, and I still don’t know how they do it on other shows fully, but it’s interesting playing opposite you because you end up working opposite of a double. That relationship’s really interesting too because you’re like, “Wait, that’s my part, but not.”

It’s been a lot of fun just breaking it down like, “OK, this is what I want to do when I’m the Evil Queen, let me remember what I’m going to do, so as Regina I know how to respond.” It’s really kind of fun. I’m learning as I go along. It’s wonderfully complicated and wonderful to play.

What can you tease about this Sunday’s episode and the Evil Queen’s part in Hyde’s plans?

Well, she’s teamed up with Hyde, which I think is a fun duo. I actually like to describe their relationship as a match made in hell, which I just thought was perfect for those two.

Regina’s teamed up with Dr. Jekyll, and she’s assisting him. He’s trying to come up with some sort of serum to stop or kill Hyde and the Evil Queen. So of course the villains learn of this, and they are on a mission to stop them. So you have like the two heroes and the two villains and the doppelgangers of one another — they’re like fighting this whole episode.

How would you describe what’s going on between Regina and Zelena and the Evil Queen?

I think Regina and Zelena (Rebecca Mader) are in a very tricky place right now. As we saw, Regina’s having a hard time with Zelena even being present. I think she really blames her for everything that has happened. She has a good case. We forget about all of that. We love Zelena because Zelena’s amazing, but we forget that she became Maid Marian, but she wasn’t, and then she got pregnant with [Regina’s] boyfriend. I mean, it’s like whoa. Now the baby is Regina’s boyfriend’s baby. I mean, it’s so complicated. And now he’s dead, and his soul has been obliterated. I think Regina’s having a really hard time.

And the Evil Queen finds her deliciously wicked and is like, “Oh my god! You’re the sister I’ve always dreamt of, and I always wanted.” They’re going to team up, and they’re going to take us down a fun path. It’s some fun stuff coming up with the Evil Queen and Zelena.

Sam Witwer Once Upon a Tme ABC

Do you know how Sean Maguire, who plays Robin, is coming back into the picture?

He’s coming back as Maid Marian! [laughs] Kidding. Twist of all twists, he wasn’t really dead.

RELATED: ‘OUAT’: The Evil Queen puts the creepy moves on Rumple

Yeah, I have no idea how he’s coming back. I’m excited to find out, but I have no clue. I have no insight past the episode that I’m filming. It’s exciting though, and I think it’s going to be great for everyone. For our audience to have one of our favorite characters back, and that’s the thing with “Once Upon a Time.” We find ways to bring characters and people we love back onto the show. I have no idea what lies ahead for Robin Hood or Regina, but I’m excited to find out.

Do you think the Evil Queen or even Regina could be under that hood?

I don’t know. Maybe? I hope not.

That would require Regina going really dark again. Does she have the potential to go there? Maybe? I think she’s going to fight it like she’s been fighting it for years. Could it be the Evil Queen? I have no idea. I really hope that it’s not Regina, but who knows?

The Evil Queen got very flirty with Rumplestiltskin. Are we going to see more of that dynamic?

Yes, you are. It’s a very strange dynamic, and I think that’s what makes it so cool … If you think about their relationship from early on, it was kind of always written that way. Especially when they first met, or at least when Regina remembers when they first met because apparently he met her as a baby as well.

There was always a flirtation or a certain kind of chemistry between them, and I think with the Evil Queen — I mean she’s the embodiment of darkness — she’s like letting all of this darkness play out. She’s like the ultimate bad girl right now. She’s having fun, she’s flirting with Gold (Robert Carlyle), she’s flirting with herself. She’s pushing everyone’s buttons, and she’s really just enjoying the taunts right now. I think with Gold, their relationship is going to lead to a really interesting place. I don’t want to give anything away but keep watching.

What can you say about the mother/son relationship between Henry and the Evil Queen which was brought up recently?

You know, I think that there’s a lot that happens that Regina doesn’t know about. There’s little visits, and you’ll see the Evil Queen is going to really try to establish her relationship with Henry (Jared Gilmore) and remind him that she is his mother. She’s equally his mother as Regina is. She really is, and we saw that last episode. She reminded him of all the things she has done for him and the memories they share.

I think Regina is going to have difficulty with that. She’s going to be fearful that Henry will fall into the hands of the Evil Queen and then what? Will we have an Evil Henry? I think she does fear that, and she’s keeping Henry close as best she can.

“Once Upon a Time” airs Sundays at 8 p.m. ET/PT on ABC. You can catch up on past episodes at ABC.com

Posted by:Lindsay MacDonald

Lindsay MacDonald is a Los Angeles based entertainment reporter with an affinity for CW superheroes. She graduated from Pepperdine University with a major in Media Studies and a borderline unhealthy obsession with TV in 2012. She would much rather spend the day binge-watching ‘The Flash’ or sorting ‘Game of Thrones’ characters into Hogwarts houses than venturing outdoors. TV words to live by: “Never ignore coincidence. Unless, of course, you’re busy. In which case, always ignore coincidence.”