With great crystal comes great responsibility! Once Upon a Time's Sunday, May 8, episode started with Zelena (Rebecca Mader) and Hades (Greg Germann) in Storybrooke after escaping the Underworld. Zelena handed over her still-unnamed child to Hades, saying she trusts him with anything. She then left to check in with her sister, Regina (Lana Parrilla), and tell her that Hades had changed his evil ways.
As if on cue, King Arthur (Liam Garrigan) showed up after escaping jail, and looked to Hades for help. King Arthur said he was "unjustly imprisoned," and Hades said he could relate. Hades then helped the only way he knows how: by killing King Arthur with the snap of his fingers.
Snow White and the Happy Reunion
Snow (Ginnifer Goodwin) was surprised to see Charming (Josh Dallas) and the rest of her family after escaping the Underworld. Emma (Jennifer Morrison) then informed her that not only did Hook (Colin O'Donoghue) not make it back, but Hades was now in Storybrooke and evil as ever. Emma said, "I made so many mistakes — I should have never gone down there," which might be the understatement of the century. Meanwhile, Regina and Robin Hood (Sean Maguire) tried unsuccessfully to convince Zelena that Hades was indeed still a villain. In disbelief, Zelena warned Regina not to hurt Hades, saying that if she did, it would be at her own peril. She then left in a huff, and in a puff of green smoke.
Now in the Underworld, King Arthur ran into Hook at the diner of the Blind Witch (Emma Caulfield). After realizing he was no longer with the living, King Arthur reluctantly agreed to help Hook find Hades' weakness in hopes of moving on to a better place.
The King Is Dead
After discovering King Arthur's lifeless corpse, Emma was ready to run off half-cocked and fight Hades. She was stopped by her father, Charming, who told her that other people deal with death "by grieving." While hiding from the others, Hades was lying to Zelena by making her think he had changed and that everyone else was out to get him. Hades then said, "I hope it doesn't come to a fight, but if they force us into it, I do have something." He then pulled out two halves of the Olympian crystal, mentioning to Zelena that it was very powerful and dangerous and that he has waited a very long time to use it.
Gold (Robert Carlyle) asked the father of Belle (Emilie de Ravin) to give her true love's kiss so she would wake from the sleeping curse, but her dad refused, saying he would rather die than help Gold. Emma showed up and stopped Gold from hurting Belle's father. She then asked Gold if he knew how to stop Hades. Back in the Underworld, Hook and King Arthur were on a quest to find the missing pages from the storybook that Hades stole, hoping that it would help them discover his weakness.
Time for a Plan
Hades was mending the crystal, now that his heart had started beating after true love's kiss. He wanted to rule Storybrooke, even though Zelena just wanted to move on and start anew. Gold was willing to make a deal for the crystal, Hades said no and Gold said, "Don't say I didn't warn you." Robin Hood and Regina finally agreed to give Zelena a second chance after they rescued Robin's daughter. The archer said he never does anything without a plan, but this time he would just have to wing it.
Hook and Arthur were in a boat in the River of Souls looking for the storybook that Cruella had hidden. Just before they reached the book, an evil spirit grabbed King Arthur by the ankle, attempting to drag him into the river. Before he could, Hook used a torch to fight off the spirit. They then placed the pages they found into the Underworld copy of the storybook, and Emma discovered the pages in the Storybrooke copy of the book. She now realized the crystal is Hades' weakness.
Fight for Your Life
Zelena caught Emma trying to break her protection spell, and Hades walked right by Regina and Robin Hood. The couple then went to save the baby, but Hades caught them and tried to kill Regina with the Olympian crystal. As a true hero, Robin stepped in front of the blast, and his soul was instantly erased from existence. And you thought your day was bad.
Zelena caught Hades as he was about to kill Regina. After a scuffle, Zelena ended up with the crystal, and Hades urges her to kill Regina. Realizing that Hades didn't actually change, Zelena turned on him and killed her true love to save her sister. Zelena and Regina embraced amid the shock of losing their true loves.
Go to the Light
Hook thanked King Arthur for his help, to which Arthur replied, "I have embarked on many a wrongheaded quest in my time. I'm just glad to finish one that was righteous." King Arthur stayed to fix the Underworld as its leader, while Hook moved on.
Zeus appeared before Hook and thanked him. He then guided Hook to where he belonged.
It's Hard to Say Goodbye
Emma, Regina and the rest of Storybrooke were at Robin Hood's funeral to say goodbye. Zelena decided to name her daughter Robin as a tribute. Emma was left alone to say goodbye, when Hook suddenly appeared behind her, alive and well.
Gold sifted through Hades' ashes and retrieved a piece of the Olympian crystal, saying to the pile of ashes, "Like I told you, this is my kingdom."
Tell Us: How will Robin's death affect Regina? And what should be next for her love life?
Once Upon a Time airs on ABC Sundays at 8 p.m. ET.
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