Henry leaves Storybrooke in search of his own story. Years later in another realm, he encounters a troubled Cinderella, changing the trajectory of his quest forever. When Cinderella's evil step-mother, Lady Tremaine, poses a threat, Henry discovers that following his heart will require him to make more difficult choices than he ever could have imagined. Years later, a young Lucy finds a disillusioned Henry at his home in Seattle, determined to make him remember his true self in order to defeat the curse afflicting the fairytale characters of "Hyperion Heights."

Emma tries to convince Aladdin to work with Jasmine to help Agrabah, while Regina teams up with Snow and David to free Archie from Zelena. Meanwhile, in the past, Hook finds himself kidnapped by the mysterious Captain Nemo and held captive aboard his submarine, the Nautilus.

Gold tells the Evil Queen she must kill Zelena, and the Queen makes a decision that will change her relationship with her sister forever. When Belle discovers Gold's plans for their son, she convinces Hook and Emma to help her steal squid ink that can immobilize him. Meanwhile, Jasmine finds a genie-less lamp that she hopes to use to save Agrabah.

When Hook finds himself trapped in another realm along with the Nautilus and her crew, he races to return to Emma before Gideon can execute the rest of his plan. In Storybrooke, Regina and Snow take Emma out to get her mind off Hook's disappearance. And in a flashback to Agrabah, Jasmine befriends Ariel, and together they set out to locate Prince Eric as the threat from Jafar intensifies.

Cinderella joins forces with a new friend; Jacinda tries to protect Lucy's community garden; Lucy tries to convince Henry that Victoria is after more than just a plot of land; Victoria makes a discovery that could alter everyone's fate.

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.

On the day of Tiana’s coronation, a confrontation with Dr. Facilier compels her to take a trip through the Bayou, where a surprising encounter changes her life and the hunt for an alligator takes a dark turn. In Hyperion Heights, Sabine reconnects with an old friend whose plans could jeopardize her culinary dreams. Meanwhile, Rogers and Weaver investigate a Blind Witch, leading them to a shocking discovery about The Coven.

Emma's life turns upside down when she is visited by Henry, the 10-year-old child she long ago gave up for adoption; Emma brings Henry back to his foster mother in a strange town called Storybrooke.

In flashbacks, Ruby and Mulan find themselves in Oz, where they meet Dorothy. After the three witness Zelena’s return to Oz, they look for a way to defeat her once and for all. However, Dorothy mysteriously disappears, and Ruby’s search for her new friend lands her in the Underworld. Reunited with the heroes, Ruby teams up with Emma, Regina and Snow to continue looking for Dorothy. Meanwhile, Snow and David struggle with not being able to be with their son, Neal, and devise a plan so that one of them can escape the Underworld.

Princess Jasmine recruits Aladdin to help her recover a secret weapon capable of breaking Jafar's hold on the Sultan and saving the city from ruin. In Storybrooke, the Evil Queen tricks Hook and the Charmings and forces Emma to reveal her secret in an effort to divide the family.

Tana seeks help from a traveling soothsayer, the iconic Dr. Facilier, in an attempt to save her kingdom. But when it’s revealed that he has an ulterior motive she’s forced to take matters into her own hands. In Hyperion Heights, Sabine and Jacinda take on a risky business venture, but the strength of their friendship is tested when Victoria interferes with their plans. Meanwhile, Ivy recruits Henry to investigate Victoria, and Roni makes a discovery that could change her relationship with Henry forever. Rogers uncovers a crucial clue in his search for Eloise Gardener.

Mary Margaret hires Mr. Gold as her attorney when Emma is forced to arrest her for the suspected murder of David’s wife, Kathryn. Meanwhile, back in the fairytale land that was, Prince Charming sets out to stop a determined and unhinged Snow White, whose memory is still clouded by Rumplestiltskin’s potion, from assassinating the Evil Queen.

Gold and Belle convince Emma to help Gideon, explaining that together they can stop the Black Fairy. Henry experiences a disorienting shift in his powers that forces Regina to seek counsel from the previous Author. Meanwhile, in Fairy Tale Land, Hook attempts to win the assistance of an old adversary by betting his most prized possession on a game of cards. And, in a flashback, the Black Fairy tortures young Gideon in hopes of molding him into the perfect apprentice.

Regina does everything in her power to force Emma out of Storybrooke and out of her and Henry's lives forever. Meanwhile, the chilling circumstances of how the Evil Queen released the curse upon the fairytale world is revealed.

As our heroes set out to stop Hyde, Emma develops a mysterious side effect, and Storybrooke becomes a haven for refugees from the Land of Untold Stories. Meanwhile, Regina and Zelena embrace their newfound sisterhood by becoming roommates, while Rumple tries to free Belle from the sleeping Curse with the help of a stranger. In flashback, Jafar confronts an afflicted Aladdin in Agrabah, and a secret about the Savior is revealed.

The Evil Queen and Hyde continue on their quest to steal Dr. Jekyll's serum; Snow looks forward to her first day back as a school teacher; and while Emma looks forward to Hook moving in with her, Hook finds himself trying to protect Belle from Mr. Gold, who has made sure she can't leave the confines of the pirate ship.

Emma and Regina formulate a plan to trap the Evil Queen in a prison of their own making, while Snow and David adjust to life without each other. Meanwhile, Zelena agrees to help Belle, and together they enlist Aladdin to steal a magical object from Mr. Gold that could protect Belle and her unborn child from him forever.

Rogers strikes a deal with Eloise despite Tilly’s fair warning, while Ivy struggles to find herself after Victoria’s death. Meanwhile, in a faraway realm, Hook confronts Captain Ahab over a legendary magical talisman which can free Alice, only to learn that his quest may have unintended consequences.

With Snow still asleep in Storybrooke, David and Hook race to stop Gideon before he can confront Emma. Meanwhile, Regina struggles with the realization that everyone, even Robin, is better off in the alternate world where the Evil Queen was defeated. And when Emma inspires a familiar face to help her and Regina return home, she discovers the power to change her fate.

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.

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.

Eager to harness her burgeoning magical skills, Robin engages in a risky relationship with Mother Gothel. Meanwhile in Hyperion Heights, Roni and Kelly strike a deal with Eloise, desperate to save Lucy from her mysterious illness. But nothing comes without a price. As things finally come to a head between Victoria and Ivy, someone may have to pay with their life.

Henry grapples with an important decision when a job prospect in New York threatens to take him away from Jacinda and Lucy, but a revelation in the case of The Candy Killer could make it even harder to leave Hyperion Heights. Meanwhile, Margot confides in Tilly, and in a flashback, Hook helps Henry find a way to prove himself to Ella.

As Storybrooke continues to welcome the new arrivals from the Land of Untold Stories, families, friends and enemies are reunited once again. When Cinderella searches for her step-family, intent on settling their unfinished business, Emma, Hook and Henry scramble to help her before it's too late. Meanwhile, Regina attempts to bribe Mr. Hyde for information about how to defeat the Evil Queen, and Snow helps Dr. Jekyll find a laboratory for his work.

Believing there isn't room in Storybrooke for both her and Regina, the Evil Queen sets out to eliminate her other half. Hook, determined to make things work with Emma, turns to his old friend Captain Nemo for advice, but Gideon torpedoes the plan before he's able to set things right.