'Once Upon a Time': Kristin Bauer on Mixing It Up With the Evil Queen and 'True Blood's' Season 5

Once Upon a Time made a splash with its premiere episode on ABC and the show has only just begun to reveal what’s in its bag of tricks. True Blood’s Kristin Bauer van Straten guest stars on Sunday’s episode as one of the queen’s oldest frenemies, Sleeping Beauty's Maleficent, and she says that will definitely stir the witch’s brew.

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“Meleficent is another one of these diva power players who isn’t afraid wielding what others may call evil,” Bauer van Straten tells The Hollywood Reporter.

“They’re just willing to take it to another level and so its fun to play all the different layers in this ‘friendship’ that she has with the Evil Queen,” she continues. “Because, they’ve got this massive history, you get into these immortal characters and they have been playing this chess game for a long time.”

On Sunday’s episode, Regina aka the Evil Queen (Lana Parrilla) will try to chase Emma (Jennifer Morrison) out of Storybrooke once and for all. And viewers will learn the circumstances surrounding the powerful curse that transported everyone to the real world and robbed them of their memories and I get the feeling that Maleficent may have played a role.

“In their long relationship, the roles are changing, because Meleficent has been sort of a mentor at times in my mind to the Evil Queen,” she says. “But when somebody wants something bad of enough, wants revenge bad enough they change… It’s a character-defining moment. We tried to find those places to show where this is a fork in the road for the Evil Queen.”

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Bauer van Straten is only currently booked for the one episode, but she might return in the future to take care of some unfinished business, which she says will become clear after Sunday’s episode.

She’ll have to balance that return with shooting on Season 5 of True Blood starting sometime in November and the actress tells us that she just received the first script this past week. “It’s pretty exciting,” she says.

She tells THR that the first episode picks up right after Season 4’s finale where the witches are finally defeated and Pam's maker Eric’s (Alexander Skarsgard) love for Sookie (Anna Paquin) has remained strong after the amnesia curse.

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“Definitely going to be more forced interaction between Pam and Sookie, I feel,” she says. “That’s the impression I get. You know there are so many story lines that you only get a little tidbit each script. But, I feel like Pam and Sookie are going to have to deal with each other.”

True Blood returns to HBO next summer. Once Upon a Time airs Sundays at 8 p.m. on ABC.

Email: Jethro.Nededog@thr.com; Twitter: @TheRealJethro