Tensions arise as Hook's ship sets sail to Neverland to search for a kidnapped Henry, while Neal travels through the Enchanted Forest with Mulan. Meanwhile, Henry finds himself on the run from the Lost Boys after Greg and Tamara are ambushed.
In Neverland, Peter Pan gives Emma a map that will reveal Henry's whereabouts as soon as she accepts her true identity, while Gold receives some unexpected advice. Back in fairy tale land, the Evil Queen presents Snow with an offer, which Charming does not want her to take.
Hook suggests tracking down Tinker Bell to help locate Pan's hideout, while Neal devises a plan in order to get to Neverland. Meanwhile, back in fairy tale land, Tinker Bell offers to help improve Regina's life.
Gold confronts Pan, while Neal finds himself back in Neverland. Back in fairy tale land, Rumplestiltskin goes in search of a missing Baelfire, who has followed a mysterious figure who steals away children with his music.
Hook tries to help save David's life as the deadly dreamshade takes it's effect. Back in fairy tale land, Killian Jones and his brother, Captain Liam, sail under orders of the King to find a powerful indigenous plant on an uncharted land that could help heal any injury.
As Henry's life hangs in the balance, the race is on to stop Pan from gaining full power from the heart of the truest believer. Back in Storybrooke of the past, Regina decides to fill a void in her life and sets out to adopt a baby.
As Hook's ship returns to Storybrooke, a well-hidden Pan puts a new plan into motion. Back in fairy tale land, Snow and Charming go in search of a mythical being that could stop Regina cold in her tracks.
Emma arrives in Storybrooke with Henry, only to discover no one remembers the past year they had spent in fairy tale land. Back in the fairy tale land during the past year, Regina and Robin Hood attempt to break into her castle, which has been overtaken by the Wicked Witch.
As the hunt for the Wicked Witch continues, she sets a plan for David into motion. Back in the fairy tale land that was during the past year, Prince Charming encounters Rapunzel and assists her in facing her fears.
Neal finds himself back in Storybrooke, while Regina discovers a possible connection with Robin Hood. Back in the fairy tale land that was during the past year, Neal and Belle attempt to find a magical solution to bring back Rumplestiltskin from the dead.
Ariel arrives in Storybrooke looking for Prince Eric, while Regina instructs Emma in magic. Back in the fairy tale land that was during the past year, Hook and Ariel search to reclaim the Jolly Roger from Blackbeard.
Zelena threatens to kill Henry if Hook doesn't kiss Emma and take her magic away. Back in the fairy tale land that was during the past year, the curse to send everyone back to Storybrooke is cast from an unlikely source.
As Mary Margaret goes into labor, the residents of Storybrooke try to prevent Zelena from stealing her newborn baby for use in her evil plan. Back in the land of Oz, Glinda tries to convince Zelena to fight her evil tendencies and join her as a protector of Oz.
In this the first part of a double episode, everyone in Storybrooke joins Mary Margaret and David as they prepare to celebrate the birth of Emma's brother but the time traveling portal that Zelena created before her demise comes to life, and takes Emma and Hook back to the Enchanted Forest before the events of the original curse.
In the conclusion of two-part episode that serves as the season three finale, Emma and Hook must find a way to return to Storybrooke, but in their quest to return, they have to find a way not to interfere or tamper with the events that lead up to the first curse, or else they risk altering the entire timeline, and could end up warping the future existence of everyone involved, including Emma, Hook, as well as Emma's family back in present-day Storybrooke.