Plot summary
The heroes arrive in the Underworld, which bears a striking resemblance to Storybrooke. Here, souls with unfinished business live, including Peter Pan and Cora. Cora offers Regina a way out, telling her she has one hour to leave on the ferry with Henry and Robin. Regina finds the soul of her father, whom Cora has threatened to send to a deeper layer of hell if she does not leave soon. When Regina's father tells her she has come too far to betray her friends now, Cora attempts to banish him.
However, as Regina has chosen to stay, Cora's attempts are ineffective, as seeing his daughter choose to stay a hero resolved his unfinished business. With his soul at peace, he is accepted into "a better place" and departs the Underworld after saying goodbye to Regina and Henry. The heroes realize they could potentially rescue all the souls here and continue their quest to find Hook with this in mind. Cora meets with the ruler of the Underworld, Hades, who wishes the heroes gone. He punishes Cora for her failure with an eternity as a miller's daughter once again. Flashbacks show Regina celebrating her birthday with a surprising visit from her mother, Cora.
Credits
Adapted from Wikipedia contributors, Once Upon a Time season 5. HTML formatting and reference markers removed.