In their continuing quest to find Peter Pan's hideout and save Henry, Hook suggests tracking down Tinker Bell in the hope that she will lead them straight to his camp. Pan reveals to Henry why he has brought him to Neverland and in the Enchanted Forest, Neal has a plan that could transport him to Emma, but it would involve using one of Robin Hood's most precious possessions. Meanwhile, in the Fairy Tale Land that was, Tinker Bell offers to help Regina improve her life.

In New York, Hook tries to make Emma remember by something very powerful: true love. In the Enchanted Forest, Regina, Snow, and Charming all team up to defeat a very powerful witch. In another world's past, a young girl learns how to use wizardry only to be hunted by a mob.

Neal finds himself back in Storybrooke and yearns for a way to reconnect with his son Henry, whose memories of his father are gone, while also trying to find his own father, Rumplestiltskin, whom he has just learned is alive but missing, and Regina discovers a possible connection with Robin Hood. Meanwhile, in the Fairy Tale Land that was over the past year, agonizing over the death of his father, Neal - with the help of Belle and enchanted candelabra Lumiere - attempts to find a magical solution to bring back Rumplestiltskin from the dead.

After Zelena steals Regina's heart, Regina casts a spell so that she can speak across the realms to her dead mother, Cora, to discover the truth about why she abandoned Zelena, and Belle stumbles across what Zelena's ultimate end game is. Meanwhile, in the Fairy Tale Land that was, young Cora is duped by a man claiming to be a prince and finds herself alone and pregnant. But a chance meeting with a real prince could lead Cora to the royal life she's always craved, but she must keep her pregnancy a secret or risk losing everything.

Hook and Emma try to find their way back to the present and correct the mistakes they made in the past.

A scared and confused Elsa from Arendelle finds herself in Storybrooke and creates a powerful snow monster for protection. Regina wonders if her relationship with Robin Hood has been completely quashed now that Marian's back in the picture. Elsa's sister wants to complete their parent's fateful journey and discover if their quest may have held the secret to containing Elsa's out of control ice powers.

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.

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.

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.

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.

Immediately after becoming the Dark One, Emma disappears and the heroes must band together to save her, but first they have to find her, which will require the help of an unlikely ally. Meanwhile, in the Enchanted Forest, Emma struggles to resist her dark urges as she searches for Merlin in the hope that he can stop her transformation. Along the way to Camelot, she gets help from the plucky and brave warrior princess Merida, as well as King Arthur and his Knights of the Round Table.

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.

Emma, David, Regina, Robin and Henry are finally back home in Storybrooke and reunited with Snow, but, unfortunately, they still have to contend with Hades, who continues to deceive Zelena as he lays out his plan to use the all-powerful Olympian Crystal to take over the town. The heroes desperately search for a way to defeat Hades while Hook does the same in the Underworld, looking for those missing storybook pages. Regina and Robin take a more direct approach, which culminates in an epic showdown that will leave our heroes forever changed.

Regina reels from the death of Robin Hood, and everyone tries to give her room to grieve, but when the heroes discover Gold has stolen Hades’ Olympian Crystal and tethered all of Storybrooke’s magic to it, they set out to stop him. Henry decides he no longer can stand all the pain magic has caused his family, so he goes rogue, with Violet in tow, to destroy magic once and for all. Meanwhile, Zelena, Snow, David, and Hook attempt to open a portal that will return Merida and the other Storybrooke guests to their homes, but things go awry, and the group winds up in a deranged new world.