"Swan Song" is the eleventh episode and midseason finale of the fifth season of the American fantasy drama series Once Upon a Time, which aired on December 6, 2015.

Also, in the end, Emma, her parents, Regina, Robin, Henry, and Mr. Gold go to the Underworld to bring back Hook.

The Enchanted Forest flashbacks with young Killian take place years before "The Brothers Jones" and the Enchanted Forest flashback with Hook and the Evil Queen take place during "Queen of Hearts", before Hook leaves for Wonderland.

Regina and Robin then run into Zelena, who vows to get custody of her daughter, only to be confronted by a group of Dark Ones who then place a mark on Emma's family and friends in a similar fashion.

At Granny’s, Mary Margaret, David, and Henry choose to spend their last hours alive, while Emma reveals her plan to Regina that she wants to sacrifice herself of the darkness inside.

Gold then hands over Excalibur to Emma and arranges for Belle to escape town and live her life.

The 21 past Dark Ones, led by Nimue, bring the residents to the lake that will take them to the Underworld, and act as a barrier to keep them from escaping.

Hook then asks Emma to kill him to destroy the Darkness, in order to allow him to die as a hero.

A sad, crying Emma goes through with his wishes and impales Hook with Excalibur, which kills all of the previous Dark Ones.

At the lake, Emma is joined by Gold, Regina, Mary Margaret, David, Robin, and Henry, as they approach the ferry to descend into the Underworld.

But make no mistake: while “Swan Song” is an undoubtedly emotional hour of television, it’s also incredibly frustrating in how it restores the status quo.

"[1] Andrea Towers of Entertainment Weekly notes in her assessment of the review: "From Camelot to Neverland, the show has never quite been able to sustain itself when it’s simply Storybrooke, as much as some of the better stories have been rooted there.

The bigger (and more interesting) question at stake is the fact that now that we’re in the Underworld, how many previously dead characters are going to get a chance to return?