Emma continues her exhaustive search for evidence that will prove Mary Margaret's innocence in the murder of David's wife, Kathryn. Meanwhile, in the fairytale land that was and before evil blackened her soul, Regina must choose between betraying her mother, Cora, and marrying for true love, or betrothing royalty and living a regal - but loveless - life; and the event that caused the Evil Queen to loathe Snow White is revealed.

Regina continues to seek a way to regain her powers; David continues his quest to find Mary Margaret and Emma; the seven dwarves discover what happens when one of the townspeople tries to leave Storybrooke's city limits.

Emma and Mary Margaret try to find a portal that would bring them back to Storybrooke; Henry tries to talk Jefferson into reuniting with his daughter; on the eve of meeting Prince Charming's mother, King George poisons Snow White.

Belle threatens to leave Mr. Gold if he doesn't change his ways; the dwarves try to find fairy dust in the Storybrooke mine; Rumplestilskin tries to save his wife from a band of pirates.

Cora tries to steal the compass from Emma and Mary Margaret; Regina and Mr. Gold must put David's life in danger in the hope that he will be able contact Mary Margaret.

Hook and Cora face off with Emma and Mary Margaret in a race for the compass; Mr. Gold and Regina plan to kill anyone who enters the portal.

When Regina is accused of murdering a beloved fairy-tale character, Emma thinks she is innocent; Prince Charming and Snow White plan the evil queen's execution.

A stranger may be a threat to the true identity of the townspeople; Cora tries to reunite with Regina.

Emma, Henry and Mr. Gold search for Gold's son in New York; Hook, Cora and Regina look for one of Rumplestiltskin's most precious possessions.

When Mary Margaret learns of Cora and Regina's plan for the dagger, she resolves to find it first; Mr. Gold continues his search for Bae; the Blue Fairy offers Snow White an enchantment to save her mother.

Cora and Regina try to overpower Mr. Gold; dark magic tempts Mary Margaret; Rumplestiltskin offers his services to Cora.

Emma returns to Storybrooke to reunite Lily with Maleficent while Regina and Robin struggle to cope with the implications of Zelena's pregnancy. When Gold's health takes a turn for the worse, Isaac looks to a new ally for help procuring the magic ink he needs to re-write history. In a Fairy Tale Land flashback, Cora returns from Wonderland to beg Regina's forgiveness on the anniversary of Daniel's murder. Cora vows to help her daughter find true love, but Regina remains suspicious of her mother's intentions.

Emma, Regina, Mary Margaret, David, Robin, Henry and Gold arrive in the Underworld, on a mission to rescue Hook, only to discover that their search will be more difficult than they had anticipated. The inhabitants of the Underworld — all souls with unfinished business and many with quite personal vendettas — hound our heroes at every turn. Meanwhile, in an Enchanted Forest flashback, a familiar face from the Evil Queen’s past returns to present Regina with the perfect birthday gift.

Now that Hades and Zelena are reunited, Hades tells Zelena that he wants a future with her outside of the Underworld. All she needs to do is heal his heart with True Love’s Kiss so they can leave the Underworld and trap the heroes there for eternity. When Regina overhears of this plan, she enlists Cora’s help to find a way to separate Zelena from Hades. However, Cora reveals a family secret that could change Regina and Zelena’s lives forever. Meanwhile, David finally meets James, only to realize that his twin is determined to seek revenge on him for stealing the life he could have had.