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.

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’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.

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 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.

The heroes join forces with an old friend of Snow's to defeat an obstacle standing in the way of finding Hook. Meanwhile, Hook encounters challenges of his own.

Emma, Snow, David, Regina, Robin, Henry and Hook continue to search for a way to free everyone from the Underworld. At the mercy of Hades, Gold creates a portal to Storybrooke, which transports Belle, Zelena and Baby Hood to the Underworld. While Zelena and Regina get into a sibling squabble, Belle is reunited with Rumple only to learn some tremendously shocking news that will change her life forever. Meanwhile, Snow and David hopelessly attempt to send a message from the Underworld to their son, Neal. In flashbacks, Hades learns about Zelena’s very special spell and pays her a visit in Oz with the intention of striking an alliance, but finds himself with more than just a partner in crime.

When a mysterious man from the Land of Untold Stories, who has a past with the Evil Queen, arrives in Storybrooke, David and Snow work together with Regina to neutralize the threat. Belle seeks Hook's help finding a safe place to hide away from her husband, Mr. Gold. The Evil Queen continues to try to win Zelena over to her side, while Emma resumes her therapy sessions with Archie and shares her terrifying vision of the future.

When Gideon resumes his mission to kill Emma and become the Savior, Gold steps in to ensure that the use of dark magic does not poison his son. Meanwhile, Robin proves willing to ally himself with anyone offering the possibility of escape from Regina and Storybrooke. Hook gathers the courage to come clean to Emma, but not before she discovers he's been keeping a secret.

After Rumple's mother learns from his fairy godmother that his destiny is prophesized, she does everything in her power to keep it from happening. Meanwhile, in Storybrooke, Rumple faces a similar delimma.

It’s Halloween in Hyperion Heights and Victoria forces Ivy to take Lucy trick-or-treating. Meanwhile, Tilly appears to be waking up from the curse and is intent on leading Weaver to the truth – but not if Victoria can help it. In a flashback, Rumple and Belle seek the answer to a prophecy that could cement their happy ending.

In an attempt to prevent a distressed Alice from running away, Henry and Ella follow her into Wonderland. Once there, Henry realizes that Ella has a surprising connection to this strange world. In Hyperion Heights, Jacinda reconnects with an old friend in a last ditch effort to regain custody of Lucy, but her decision to enlist outside help could put a strain on her burgeoning relationship with Henry.

Rogers works to prove Tilly’s innocence in the case of the Blind Baker’s death, while Ivy attempts to make amends with Anastasia, and Samdi makes a revealing confession to Roni. Meanwhile, in a faraway realm, Alice forms an unbreakable bond.

Roni enlists Lucy’s help to wake Henry and stop Gothel, but things don’t go as planned. Meanwhile, Rogers and Weaver go to Margot in hopes of freeing Tilly before her magic can be used to power the spell. In a flashback, Young Henry struggles to decide what path to follow until a mysterious phone call helps put him on track.