Actors Ginnifer Goodwin And Josh Dallas, Right, From The TV series 'Once Upon A Time.'
Actors Ginnifer Goodwin and Josh Dallas (R) from the TV series "Once Upon A Time&" arrive at the 15th Annual Costume Designers Guild Awards in Beverly Hills February 19, 2013. Reuters

"Once Upon A Time" Season 4 is taking a long hiatus, leaving fans without a new episode this week. Showrunners Adam Horowitz and Edward Kitsis described the villains of the next OUAT chapter, hinting at more complex villains and more convoluted schemes. Meanwhile, Operation Mongoose moves forward.

Spoiler alert: This Once Upon A Time Season 4 update contains spoilers. Read at your own risk.

Regular viewers of ABC's Once Upon A Time Season 4 saw the three "Queens of Darkness" in Episode 12, aptly titled, "Heroes and Villains." This episode ends the "Frozen" arc and bids goodbye to Queen Elsa (Georgina Haig), Anna (Elizabeth Lail) and Kristoff (Scott Michael Foster), who have all gone back to Arendelle.

OUAT 4x12 reveals that the Queens of Darkness once tried to get Rumplestiltskin on their side. The latter said he's the kind of villain who works alone. After Belle (Emilie de Ravin) banished Rumple from Storybrooke, however, his tune has changed. What happens next?

"Heroes always work together and never put their ego first. Villains so often put their ego first and lose," Kitsis told Entertainment Weekly. The statement previews some inevitable conflicts in Team Villains.

That the Queens of Darkness have "slightly aligned agendas, but wanting things for themselves" is enough material for some fascinating stories in Once Upon A Time Season 4, Adam Horowitz told EW.

"It's a very formidable team of evil coming our way," Kitsis told TV Line.

Team Mongoose vs Queens of Darkness

Rumplestiltskin and the next chapter's featured villains will be confronting the Sorcerer, as implied in the final act of Once Upon A Time Season 4, Episode 12. Meanwhile, Henry (Jared S. Gilmore), Regina (Lana Parrilla), and Emma (Jennifer Morrison) have decided to do the same.

"Operation Mongoose" pulls in the longtime viewers to take a very good look in the evolved relationship between Regina and Emma. The (former) Evil Queen and the Saviour join forces with their son to have a dialogue with the Author and demand a happy ending.

Between Operation Mongoose and the unfolding evil schemes, guest characters like Princess Aurora (Sarah Bolger) and Ariel (JoAnna Garcia Swisher) are expected to return.

"You will see [Ariel] within the first half of [Once Upon A Time Season] 4B. There may be some other returns that we're not ready to confirm yet, from our past years," Horowitz told TV Line.

Once Upon A Time Season 4 New Episode Airs Mar. 1

Fans will have to wait for over two months before the ABC fantasy drama returns. The next new episode of Once Upon A Time Season 4 airs on Mar. 1, according to the network's website.

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