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, Episode 12, titled "Heroes and Villains," airs Sunday, Dec. 14, on ABC. Regina and Emma are set to go against Rumplestiltskin, for Henry and for Hook's heart; while Marian's fate will soon be revealed. Meanwhile, three evil queens are expected to set foot in Storybrooke.

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

"In the aftermath of the Spell of Shattered Sight, the townspeople try to reorganize their lives and Regina faces a difficult decision. Meanwhile, Gold executes his plan to leave Storybrooke with Belle and Henry. In the past, Belle receives an unexpected visitor," reads the Once Upon A Time Season 4, Episode 12 synopsis on TV.com.

This week's new OUAT episode serves as the winter finale of the fantasy drama, which means avid viewers can expect one or more cliffhangers.

Regina & Emma vs Rumplestiltskin: For Henry, For Captain Hook

In the previous episodes, Rumplestiltskin aka Mr Gold revealed to Captain Hook his plan to free himself from the dagger's hold. Going in this direction, he would also be taking Belle and Henry out of Storybrooke. Lana Parrilla dished some teasers on this Once Upon A Time Season 4 plot.

"[Regina] doesn't know that Rumple has this plan under his sleeve to take her son away. However, if or when she finds out, it will not unfold prettily. She's not going to let Rumple just take her son away, Parrilla, who plays the (former) evil queen, told Entertainment Weekly.

Emma Swan is expected to team up with Regina to fight Rumple for Henry in the second half of Once Upon A Time Season 4. Aside from Henry, Emma has another reason to confront the Dark One: Captain Hook's heart.

"(E)ventually, somehow Emma is going to help [Captain Hook] get his heart back," Jennifer Morrison, who plays Emma Swan, told ET Online.

Robin Hood, Marian, Regina: A Happy Ending For Someone

Since the Snow Queen (Elizabeth Mitchell) has died, it is presumed that Robin Hood's wife, Marian, is no longer frozen. Robin Hood's decision will be revealed this Sunday in Once Upon A Time Season 4, Episode 12, Parrilla also told EW.

The triangle of Robin Hood, Regina, and Marian is about to end in a happy ending for someone, and a cause of heartache for another.

The Queens Of Darkness in Once Upon A Time Season 4 - Second Half

Three evil queens from various fairy tales are about to be the big bad villains of the second half of Once Upon A Time Season 4. The showrunners call them the Queens of Darkness.

Maleficent (Kristin Bauer van Straten), Cruella de Vil (Victoria Smurfit) and Ursula (Merrin Dungey) will all have something against Regina. Some OUAT fans are speculating the three would recruit Regina into their regally dark sorority.

"(W)e wanted the second half to be villains in search of their happy endings. We always wanted to bring Maleficent back. We thought, 'What is the greatest team of evil we could gather to go up against?'" Once Upon A Time showrunner Edward Kitsis told EW in a separate interview.

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