"Where Bluebirds Fly" is the eighteenth episode of the sixth season of the American fantasy drama series Once Upon a Time, which aired on April 23, 2017. In this episode, Zelena is tempted with an offer by the Black Fairy that could put her in a dangerous situation that prompts Regina to be drawn into the chaos, while Emma and Hook's wedding plans are made more chaotic by Snow and David. Meanwhile, Zelena's past with a cursed woodcutter, her quest to find him a heart, and her consequences afterwards, are revealed. Plot Opening sequence The Emerald City of Oz is seen in the forest. Event Chronology The Storybrooke events take place after "Awake" while the events in the Land of Oz occurs during the flashbacks that took place between "Sisters" and "It's Not Easy Being Green" and later on in the recent timeline between "Heart of Gold" and "Our Decay." In The Characters' Past In Oz, a young Zelena is testing out her magic on a bird's nest by restoring it back on top of a tree after a group of kids knocked it off. When a young boy named Stanum sees Zelena, he tells her that he likes her, regardless of whatever the children say about Zelena, who they see as a freak. Flash forward years later, where a now adult Zelena (now the Wicked Witch at this point) receives a surprise visit from an adult Stanum, this time requesting her help. He explains that Wicked Witch of the North cursed him and he is slowly turning into a tin man. Stanum is seeking out the Crimson Heart, which could restore him to human form, but moments after Zelena turn him down, Stanum accuses her of being afraid, prompting Zelena to change her mind. During their quest, Stanum tells Zelena that she doesn't have to be lonely but she is doing her best to deny his advice. Suddenly, a lion comes out of nowhere to attack Stanum, and Zelena uses her magic to make the lion go away (at this point the lion has become as Zelena would put it, cowardly). When they finally arrived to the location of the Crimson Heart, the two learned that the only way to make it work is through the absorption of another person's magic. Unfortunately, Zelena's actions and selfish greed for magic causes her to betray Stanum, whom she suspects is aligned