In Storybrooke, Emma has disappeared and Mr. Gold is in a coma. Before the Sorcerer’s Apprentice dies, he gives the heroes a magic wand that can open a portal to find Emma but it can only work through a combination of light and darkness. Regina tries to make it work but she can’t. Hook points out that she’s lost her dark edge. They realize they need Zelena to make the wand work but she refuses to help unless they take off the bracelet keeping her from using magic. Regina refuses.
In the hopes of saving Emma, Hook and Henry work together to sneak into Zelena’s cell but she tricks Hook and uses his knife to cut off her own hand, thus removing the bracelet and then magically reattaching her hand. Now on the loose, Zelena masquerades as Regina and tries to trick Robin Hood but, through the power of true love, he immediately knows it’s not Regina.
Zelena uses her magic to subdue Robin and bring him to the town square. She threatens to kill him if Regina doesn’t give her the wand. Regina makes the switch. Zelena opens a portal, planning to return to Oz with her unborn child but the power needed to open the portal weakens her and Regina gets the upper hand. Taking back the wand, Regina and company use the portal to go back to the Enchanted Forest to find Emma.
The portal takes the form of a tornado which transports Granny’s to the Enchanted Forest with everyone inside: Regina, Robin, Roland, Snow White, Prince Charming and their baby, Hook, Granny, and Grumpy.
In the Enchanted Forest, Emma fights her dark impulses which have taken the form of Rumpelstiltskin. She needs to get to Camelot to find Merlin because he can help her. Along the way she comes across Princess Merida who is chasing a Will of the Wisp to use it to save her brothers but Emma needs it to take her to Merlin. The Dark One encourages Emma to kill Merida but she fights the urge.
Merida offers to share the Will of the Wisp with Emma but the Dark One tells her it won’t work that way and Emma falls further under his spell, eventually convincing Emma to take Merida’s heart. Before she can crush it, Hook and the rest of the Storybrooke arrive and Hook convinces her to stop.
Emma asks her mother to keep the Dark One’s dagger to keep her under control but Snow tells her to keep it, believing the decision must be hers. Emma agrees. They all make their way to Camelot where the King has been searching for the top part of the Sword in the Stone which has been missing. It’s actually the Dark One’s dagger.
Six weeks later, everyone turns back up in Storybrooke. They are dressed in clothing from Camelot, except for Emma who is know the Dark One. Emma tells them they're is no longer a savior. Her friends and family have failed her and they will be punished.