'Once Upon a Time': Zelena and Regina Face Off in 'Old-School Showdown' (Exclusive Video)

The showdown between Wicked and Evil is coming.

Zelena and Regina face off in Sunday's Once Upon a Time and it's fair to say their encounter gets nasty fast. The Hollywood Reporter exclusively debuts a scene from the Zelena-centric hour, "It's Not Easy Being Green," which sees the two witches' heated confrontation in front of the entire town. The episode also features a trip to the land of Oz and answers questions about Zelena's past (among them, why she's green and why she's wicked).

Rebecca Mader, who plays Zelena, had fond memories of the verbal (and physical) beat down between Wicked and Evil. "When I saw the previews Sunday night I was dying laughing over the way they did it -- like a proper Western," Mader tells THR. "It was a real old-school showdown and that's what viewers are in for. It's an old-school, mano-a-mano showdown."

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Mader suggests that though the Wicked Witch seems far more ruthless at the moment, things may shift as past grievances come to the forefront. "It's these two different dark sides coming together and seeing who's going to win," the actress says. "It's like watching a boxing match."

The scene opens with Charming attempting to bring the residents of Storybrooke to safety before Zelena "takes it out on all of us," as Tinker Bell so eloquently warns. But Zelena, with Rumplestiltskin in tow as her puppet, arrives in the knick of time: "This show needs an audience," she declares before dropping a wicked munchkin zinger. It isn't long before Regina shows up to the party, already aware of her familial ties to Zelena. "But I still have one question: What the hell did I ever do to you?" Regina asks tersely. "Isn't it obvious?" her sister says in response. "You were born." Slaaaaap!

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Zelena's presence in Storybrooke lights a fire under Regina. "For Regina to have Zelena come along, it's reawakened that delicious side of the Evil Queen," Mader says. "She's got someone to fight again. It brings Regina and the Evil Queen's moxie back."

But with Zelena in possession of the dagger and Rumple under her guise, it will take a lot for Emma Swan and Co. to topple her. "It's the ultimate power position to be in," Mader says. "I've got the dagger and I'm controlling the Dark One. It's the best position one could hope for on the show. He's my best wingman at this point, even more helpful than my Flying Monkeys."

Once Upon a Time airs Sundays at 8 p.m. on ABC.

Email: Philiana.Ng@THR.com
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