Plot summary
In Storybrooke, Gold reveals to Emma and Snow that the Black Fairy is his mother, and that the Dark Curse Regina had cast was created by the Black Fairy. Emma agrees to help Gideon kill the Black Fairy, but is double-crossed by Gideon and left to die at the hands of a giant spider before Gold saves her. Gideon opens a portal, allowing the Black Fairy to slip through into Storybrooke. Meanwhile, in the Enchanted Forest, Hook wagers the Jolly Roger for a magic bean in a game of cards with Blackbeard.
As Blackbeard and Hook go through the portal, it malfunctions thanks to Gideon and the duo ends up in Neverland, on the run from the remnants of Peter Pan's Lost Boys. Henry experiences a disorienting shift in his Author powers, so he and Regina seek help from the previous Author, Isaac Heller. Isaac reveals to Regina and Henry that they are nearing the end of the story in which the savior must fight the Final Battle. Flashbacks reveal the abuses the Black Fairy inflicted on Gideon, and that the Black Fairy is controlling Gideon to kill Emma via his heart.
Credits
Adapted from Wikipedia contributors, Once Upon a Time season 6. HTML formatting and reference markers removed.