ABC just shared details on the two-part special, which airs November 15 from 8 to 10 p.m. Here's the rundown on the first hour, Season 5, Episode 8, "Birth," which includes the return of Dr. Whale/Victor Frankenstein:
The "Birth" guest cast includes Beverley Elliott as Granny, David-Paul Grove as Doc, Michael Coleman as Happy, David Anders as Dr. Whale, Ingrid Torrance as Nurse Ratched, Elliot Knight as Merlin, Liam Garrigan as King Arthur and Joana Metrass as Guinivere.
Tensions in Camelot come to a head when Merlin, now under Arthur's control, delivers an ultimatum to Emma: hand over the Dark One dagger and the Promethean spark or he will kill her entire family. Refusing to give in, Emma and our heroes face off against Arthur, Merlin and Zelena in an epic battle of magic and will. Just when the end is in sight, Emma is forced to make a gut-wrenching choice that no one saw coming.
Back in Storybrooke, Zelena's pregnancy mysteriously accelerates and Hook goes to new and desperate lengths to get answers from the Dark Swan.
Here's what you need to know about the second hour, Episode 9, "The Bear King," which features the return of Mulan and Red/Ruby:
"The Bear King" guest cast includes Meghan Ory as Red/Ruby, Beverley Elliott as Granny, Jamie Chung as Mulan, Amy Manson as Merida, Glenn Keogh as King Fergus, Caroline Morahan as Queen Elinor, Lily Knight as Witch, Richard Stroh as Edgar, Paul Telfer as Lord Macintosh, Marco D'Angelo as Lord MacGuffin, Josh Hallem as Lord Dingwall, Matthew Olsen as Brother #1, Jordan Olsen as Brother #2, Colton Barnert as Brother #3 and Liam Garrigan as King Arthur.
Zelena and Arthur journey to DunBroch on a mission to retrieve an enchanted relic that will provide the advantage they need to vanquish Emma and our heroes. Their path will cross with Merida's, who is on a journey of her own to pay a debt that her father, King Fergus, owed to the Witch when he died.
Merida enlists the help of two friends, Mulan and Ruby, but, in order to satisfy the Witch and save DunBroch, she first must discover the identity of the knight who killed her father. In flashbacks, Merida learns about bravery and honor as she trains for combat and rides alongside Fergus into the infamous battle that claims his life.
The next episode after the two-part special is called "Broken Heart," which gives us some not-so-pleasant clues, and it will be followed by the midseason finale, "Swan Song." (Will Emma die? Just a theory.) When OUAT returns in 2016, we'll get the 100th episode, "Souls of the Departed," probably taking us into the Underworld.
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