"Mother's Little Helper" is the sixteenth episode of the sixth season of ABC's Once Upon a Time and the one-hundredth and twenty-seventh episode of the series overall. It aired on April 9, 2017. The teleplay was by Paul Karp, and story by Edward Kitsis & Adam Horowitz and it was directed by Billy Gierhart.
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.
The spider-infested pillars from the lakeside mansion is seen in the forest
The Dark Realm events involving Gideon take place after "Changelings" and before "Wish You Were Here", while the Storybrooke events leading up to Gideon's backstory and Hook's adventures in the present day Enchanted Forest take place after "A Wondrous Place" and Hook's return to Neverland take place after "The New Neverland".
In the Dark Realm
In the Dark Realm, the Black Fairy has received the baby Gideon, who she just stole from the Blue Fairy, and she places the child with one of the child laborers. As the years goes by, a young Gideon is now a prisoner and befriend another boy, Roderick. Gideon vowed to protect his friend, but when he lashed out at the Black Fairy, she punished Roderick instead as a way to torment her grandson.
On Gideon's 28th birthday, the Black Fairy tells her grandson how proud she is of him, when she noticed one of keys are missing, so she sends Gideon to go after the person responsible. When Gideon discovers that Roderick (who is still a slave) was the person who stole the key, Roderick convinces Gideon to become a hero by defeating the Black Fairy, and tells him that his grandmother is trying to harvest more magic dust after using up the last one. Gideon apologized to Roderick for what happened when they were young and offered his aid. Roderick then tells Gideon that he needed the power of The Savior (Emma), which requires a magical orb in order to reach her.
When Gideon and Roderick find the orb and is ready to contact Emma, the Black Fairy appears. It turned out that she had it all set up to test Gideon. When Gideon decided to defend himself, the Black Fairy responded by turning Roderick into a bug and she squashed him. She then revealed that she was after Emma all along, so she takes Gideon's heart and orders him to find and kill Emma, then bring the Hrunting sword back to her which will free her from the Dark Realm.
In the Enchanted Forest and Neverland (Present Day)
At a pub, Hook comes across Blackbeard and the two make a deal, with Hook needing a magic bean and Blackbeard needing a ship, but this one is done over a game of cards, only for Hook to lose to his fremeny. When they walked over to the dock, The Jolly Roger is nowhere to be found as it has disappeared into another realm, so the two take the bean and it sends them to another realm. However, the portal sends the pirates to a place that Hook is very familiar with: Neverland. When they see the Lost Boys (who chose to stay behind in Neverland the last time they were there) they chase after them, Hook and Blackbeard make to the shoreline but when they reach and see a boat Blackbeard ends the truce by knocking Hook out and escaping with the boat. Hook then continues to run as the Lost Boys chase him.
In the Present Day, Gideon tells Emma that he needs her to help him defeat the Black Fairy and as long as he has the napkin with her tears, Hook will not return to her. Emma and Snow then visit Gold and Belle at the Pawn Shop, where despite a plea from Gold and Belle to spare Gideon's life and Emma's doubts, they do come to a truce that Emma should partner up with Gideon, as Gold tell Emma about the Black Fairy and what she is capable of as she is also Gold's mother.
Later that night at the clock tower, Emma meets with Gideon and agreed to help, on the condition that they exchange the spell to bring Hook back and Hrunting. Gideon then brings Emma through a door that can serve as a portal for Hook to return through. However, just moments before the spell is activated a giant spider comes through the portal and they run for cover, with Gideon apologizing to Emma for trying to kill her. As their attempts to escape are blocked by spiderwebs, Gideon pushes Emma into one and he takes the sword from her, allowing Gideon to disappear while Emma uses her magic to fight off the spiderwebs until Gold appears and helps Emma destroy the spider, but at that point Gideon has escaped into the portal
Hours later, Emma and Snow confronted Gold and Belle, but Emma is not convinced about Gideon being saved, prompting Gold to threaten Emma if she endangers Gideon, and as Emma and Snow leave, Gold tells Belle that he still has faith in Gideon. Meanwhile back at the clock tower, the portal open for a brief moment, allowing the Black Fairy to enter Storybrooke.
In-between the events, Regina is attempting to reverse the sleeping curse with help from Henry. When he starts taking notes on what items Regina needed, he starts writing in a possession-like state before he passes out and when he comes to, Henry has to idea what happen to him. They then pay a visit to Isaac, who is now locked up at Storybrooke General Hospital. As they demand Isaac to tell them about why Henry is starting to be possessed, Isaac refuses to tell unless he is given tickets to see Hamilton. When they refused, Regina and Henry leave, only to have Isaac tell the two that as long as Henry is possessed by the irrational powers they'll become worse, so he agrees to tell them why on condition that he is freed from his cell. Hours later at the city limits, Regina and Henry gives Isaac a car that will allow him to leave town. As part of his agreement, Isaac tells them to look at the "Once Upon a Time" book, and when Henry reads the final chapter, he discovers that it details the final battle, and Emma will be part of that story.