Marian falls under a freezing curse and the townspeople believe that Elsa is responsible. When Emma and David go to Robin's camp to look for clues, they find Will Scarlet, who leads them to the culprit. Meanwhile, in the Arendelle of the past, Elsa and Kristoff go to find the urn that Hans plans to use to imprison Elsa, and encounter the Snow Queen.

Hook discovers that magic always comes with a price after he makes a deal with Mr. Gold to re-attach his hand so that he can embrace Emma with both hands on their first real date. And back in the fairy tale land of the past, Rumplestiltskin uses Anna to help him acquire a magical box from the sorcerer’s apprentice.

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 captures the Snow Queen and learns that they are more alike then she can possibly imagine. In arendelle of the past, Ingrid discovers her deadly ice powers and makes a pact with her two sisters to protect and always be there for one another – no matter what.

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.

The Snow Queen attempts to pit Anna and Elsa against each other; with her powers out of control, Emma seeks assistance from Gold; Regina's quest takes a surprising turn.

As Storybrooke descends into chaos as the Snow Queen's spell takes hold, Emma and Elsa try to trick Regina into destroying the ribbons so that they can attack the Queen. In the past, Ingrid adopts Emma and attempts to show the girl that she's a powerful sorceress.

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.

David and Mary Margaret suspect Cruella and Ursula have come to Storybrooke looking for something more than their own happy endings – something that threatens to reveal a secret they thought was long buried. Emma begins her own investigation of Cruella and Ursula, but she can’t shake the feeling that her friends and family are keeping something from her. Regina and Henry continue their search for the Author, turning to Pinocchio and Marco in the hope Pinocchio might remember a clue that will help them. Meanwhile, in a flashback to Fairy Tale Land, Snow and Charming cross paths with the Queens of Darkness as the threat of the Evil Queen’s Dark Curse hangs over all of them.

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.

Hook leverages his complicated history with Ursula to find out what she knows about Gold’s endgame. Gold and the Queens of Darkness torture August for information about the Author as Emma, Mary Margaret and David race to find them. Regina grows concerned for Robin Hood’s safety while she struggles to maintain her cover with the villains. In a Fairy Tale Land flashback, when a restless young Ursula enlists Hook’s help to run away from home, she soon learns it isn’t wise to trust a pirate.

Emma is still reeling after learning the truth of her parents’ history with Maleficent, but she must focus on finding the Author, who is running loose in Storybrooke, before Gold does. When Gold’s quest for his happy ending grows more urgent, he blackmails Regina into helping him. In a Fairy Tale Land flashback, Robin Hood learns what it means to be an honorable thief when he accepts a proposition by Rumpelstiltskin to travel to Oz to steal a valuable magic elixir from the Wicked Witch.

Emma’s potential for darkness is looming over everyone, but when Emma realizes Maleficent’s daughter Lily is in fact her closest friend from her foster care days, she resolves to find Lily and reunite her with her mother. Regina joins forces with Emma and together they set out to track down Lily and to warn Robin about Zelena. However, neither of them is prepared for the harsh realities they’ll encounter in the outside world. Meanwhile, in Storybrooke, Gold faces a crisis involving Belle. In a foster care flashback, things are looking up for young Emma with her new family until Lily’s appearance threatens to destabilize everything.

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