ABC invites new and devoted "Once Upon a Time" viewers to take another look at this popular fantasy series in anticipation of the exciting fourth season premiere. The special will take a look at the role that family plays in the show, our heroes' journey from breaking the curse to the ramifications of magic in our world, travelling to Neverland to save Henry from an evil Peter Pan, their battle with The Wicked Witch of the West, and the upcoming presence of Elsa, the Ice Queen from Arendelle, in Storybrooke.

While desperately trying to find her sister Anna, Elsa accidentally traps them both inside an ice cave. Regina secludes herself from the town and Henry. With the townspeople considering Mary Margaret their leader, she faces her first leadership task in trying to re-start a generator and restore the town’s electricity after Elsa freezes and damages the power lines. Anna tries to teach a meek David to fight Bo Peep.

Emma tries to convince a reluctant Regina to help her find the Snow Queen, only to discover that Regina is lying to her about Sidney's whereabouts. Meanwhile, David convinces Mary Margaret to go on a date, but the date turns into a hunt when Will escapes his jail cell. In the past, Emma befriends another young orphan who isn't all that she seems.

Emma’s powers run amok and she turns to Gold for help, Elsa and Anna’s relationship is tested, and the Snow Queen’s agenda is revealed.

Emma’s powers run amok and she turns to Gold for help, Elsa and Anna’s relationship is tested, and the Snow Queen’s agenda is revealed.

In the aftermath of the Snow Queen’s spell, our heroes try to pick up the pieces and Regina has to make a difficult choice. Hook’s fate hangs in the balance as Gold’s quest for power threatens everything he holds dear. And, in the Enchanted Forest flashback, an intrusion during Belle's stay at Rumplestiltskin's dark castle will wreak havoc in both the past and the future.

In order to infiltrate the Queens of Darkness as a spy for the heroes, Regina must prove she’s still willing to get her hands dirty. Meanwhile, Emma, David and Mary Margaret scramble to keep tabs on their undercover operative. Hook requests an unusual favor from Belle as Henry makes progress on his search for the Author. In a Fairy Tale Land flashback, Regina befriends Maleficent and helps her to rekindle her lost spark.

Emma returns to Storybrooke to reunite Lily with Maleficent while Regina and Robin struggle to cope with the implications of Zelena's pregnancy. When Gold's health takes a turn for the worse, Isaac looks to a new ally for help procuring the magic ink he needs to re-write history. In a Fairy Tale Land flashback, Cora returns from Wonderland to beg Regina's forgiveness on the anniversary of Daniel's murder. Cora vows to help her daughter find true love, but Regina remains suspicious of her mother's intentions.

The Author proves to be a formidable wild card and forges an alliance with Gold. Emma, her parents, Hook and Regina scramble to stop them, but when Gold and the Author turn the tables on heroes and villains alike, the prospect of any happy outcome appears worlds away. Henry discovers he has big shoes to fill as he steps up to save his family before the story’s final page is turned. It’s a race to the finish, and everything culminates with a shocking twist that will leave the residents of Storybrooke reeling

In an effort to protect Emma, Regina steps up in a surprising way that will test her mettle as a force for good. King Arthur and Queen Guinevere throw a royal ball to welcome the heroes to Camelot, but when the celebration takes a deadly turn, David and Robin must leap into action or lose a crucial asset in the fight to save Emma. Back in Storybrooke, Hook deploys a tried-and-true technique in hopes of bringing Emma back to the light while the heroes discover that some unexpected baggage has followed them home from Camelot.

In Camelot, as Mary Margaret and David attempt to retrieve the Dark One dagger, Emma uses a Dreamcatcher to look into the past to see how Merlin was transformed into a tree. Together, Emma and Regina figure out the critical ingredient they must acquire to free Merlin, but it's a race against Arthur, who does not want Merlin released. Meanwhile, with encouragement from his moms, Henry musters up the courage to ask Violet on a date. Back in Storybrooke, the heroes break into Emma's house hoping to locate Gold, but what they find will give them a glimpse of Emma's end game. Far from prying eyes, Merida sets about the mission Emma has tasked her with and begins molding Gold into the hero they need to draw Excalibur.

In a Camelot flashback, Hook becomes a Dark One and his lust for revenge against Rumplestiltskin is reignited. When Emma and Hook disagree about their best course of action, the final pieces of the puzzle are revealed as events in Camelot catch up to the present and we witness a charged confrontation between the forces of light and dark that sends our heroes on a collision course with destiny. Meanwhile, in Storybrooke, Hook’s centuries old lust for revenge against Gold puts both of their fates in jeopardy while Emma’s love faces the ultimate test as she tries to convince Hook to turn away from the darkness before she, Mary Margaret, David and Regina embark on a new mission as an unsuspected evil is released.