The Evil Queen decides to cast her dark curse, to ensure she gets her Happy Ending. All magic, however, comes with a price. A man she had feelings for, and develops stronger feelings for, during the curse, Killian Jones, doesn't remember her one bit.
The curse has made him bitter, in this world, bitter and alone, and closed off to forming a relationship. Regina must work to undo her own curse, by finding the Savior, if she wants to have a chance at her real happy ending.