ABC has released a plot synopsis for the upcoming winter finale of Once Upon a Time, which includes something from the Enchanted Forest of the past potentially coming back in the future.

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The winter finale, titled Heroes and Villains, features the town of Storybrooke recovering from the Snow Queen's (Elizabeth Mitchell) Spell of Shattered Sight.

"In the aftermath of the Snow Queen's spell, our heroes try to pick up the pieces and Regina [Lana Parrilla] has to make a difficult choice," the synopsis reads.

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Meanwhile, Hook (Colin O'Donoghue) is still in harm's way while Mr. Gold (Robert Carlyle) continues his "quest for power" which ultimately "threatens everything he holds dear."

Also, in the Enchanted Forest in the past, "an intrusion during Belle's [Emilie de Ravin] stay at Rumplestiltskin's dark castle will wreak havoc in both the past and the future, on the winter finale."

The synopsis also reveals that the three big villains set to star in the second half of the season will be guest starring in this episode. Kristin Bauer van Straten (who plays Maleficent), Victoria Smurfit (Cruella De Vil) and Merrin Dungey (Ursula) are all slated to guest star in this episode.

It's possible that the "intrusion" at Rumple's castle is what causes the three iconic villainesses to enter the future/Storybrooke.

This episode will also include Elsa (Georgina Haig) and Anna's (Elizabeth Lail) return to Arendelle, concluding the big Frozen arc.

Once Upon a Time airs the winter finale Sunday, Dec. 14 at 8 p.m. ET/PT on ABC.

Watch the promo for the next episode of Once Upon a Time here:

Tags: Once Upon A Time television ABC