In the fairy tale land, Snow crushes Charming's heart in order to enact the dark curse so that they can get back to Emma who is the only one who can defeat the Wicked Witch. Then Regina splits Snow's heart in two so that Snow and Charming can both use it to live.
Before the dark curse comes to fruition, the Wicked Witch enacts a memory spell so they won't remember how to defeat her. She takes a potion to retain her memories and gives the other half to her captive, Rumpelstiltskin. Neal emerges from Rumpel's body before Rumpel can take the potion. He sends it to Hook with the note to find Emma.
In Storybrooke, Snow finds the story book in the hopes that it will help Henry believe since they believe Emma's true love kiss for Henry will only work if he believes in magic.
Zelena tries to kill Henry when Hook fails to kiss Emma but Emma's magic saves him. Henry takes the book and remembers everything but it isn't Emma's kiss that breaks the memory curse, but Regina's.
Emma is furious at Hook for not telling her about Zelena's curse. Snow and Charming agree Hook can't be trusted when they don't know who sent him the memory potion and instructions to save Emma.