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The episode begins with Rumpelstiltskin making a last-minute deal with the Snow Queen. The curse is supposed to make everyone in town hate one another and tear each other apart, leaving only the Snow Queen, Emma, Elsa…and the immortal Rumpelstiltskin. He warns that if she doesn’t let Belle and Henry leave with him, he will spend the rest of his life in Storybrooke trying to kill her. She agrees that the three of them can leave town before the curse takes effect.

Meanwhile, everyone else is in the clock tower watching the curse swell in the distance. Regina tells them that the curse should hit town by sundown and Emma suggests that they get everyone out of town before then.

The only problem with that plan is the giant wall of ice trapping everyone in. When David discovers that they can’t break the wall down, everyone decides to split up and warn other townspeople. Elsa becomes hopeful when she finds Anna’s snowflake necklace at the foot of the wall.

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Belle tells Emma and Elsa that there’s no way to stop the spell, but a counter-spell can be created using people under the curse. Elsa suggests that they use Anna’s necklace to find her and use her to create the counter-spell.

Back in Arendelle, the ice covering Anna and Kristoff melts, but Anna quickly realizes that urn Elsa was trapped in is gone. She finds a piece of straw on the ground and suspects that Rumpelstiltskin has the urn, but before they can go find him, Hans and his brothers — now unfrozen — come in to take over Arendelle and lock them up. Anna and Kristoff are able to fight them off and escape.

Hook stands on the docks as he watches the ice wall go up in the water, trapping people in by sea and land. Rumpelstiltskin then shows up to tell Hook — forced to serve Rumpelstiltskin because he has Hook’s heart — that he needs to trap the fairies in the Sorcerer’s hat so he can get enough power to free himself of the dagger and leave town with Belle and Henry. Hook realizes that Rumpelstiltskin is destroying the town’s only chance of breaking the curse, but Rumpelstiltskin doesn’t care.

Regina and Henry go to Robin’s camp to warn him and his men about the curse. As Henry and Will Scarlet tell everyone, Regina tells Robin about her fear of becoming who she used to be when the curse hits. She says that only he and Henry look at her without hate or fear from when she was the Evil Queen.

Emma and Elsa use a locator spell on Anna’s necklace and it begins leading them towards the library.

After escaping the castle, Anna and Kristoff begin looking for Rumpelstiltskin and in order to find them, Anna suggests that find a “wishing star.” But to get one, they have to negotiate with a pirate named Blackbeard.

Emma and Elsa go into the caves below the library. The necklace grows brighter as they get closer, but then they hit a wall. Elsa wants to use her power to break it down, but Emma says they’ll find another way.

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Anna and Kristoff find Blackbeard and he agrees to give them a “wishing star” in exchange for his weight in gold. Unfortunately, the whole exchange proves to be a trap because Hans and his brothers show up.

Grumpy, Regina, Mary Margaret, Emma and Elsa look over the cave maps to see how they can get to Anna. David shows up to tell them that the fairies said they could also extract pieces of the curse from Anna’s necklace, but it would destroy the necklace. As Grumpy puts it, do they “save the town or find the sister?”

Hook and Rumpelstiltskin go to Granny’s to capture all the fairies, but Rumpelstiltskin tells Hook to wait in the back while he gets Belle out. When she refuses to leave because she’s busy helping the fairies, he politely agrees to wait for her.

Back in the library, Regina convinces Mary Margaret that they have to destroy the necklace in order to save the most people. Emma tells Elsa the bad news and gets the cloth holding the necklace. But, Elsa secretly kept the necklace and heads back to the caves below the library.

The rest of them take the “necklace” to the fairies, but soon realize that they’ve been tricked. A frustrated Regina says she “should know better than to trust blondes by now.” Emma — the only one refusing to give up — decides to go help Elsa find Anna because it’s their only hope now.

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Elsa uses her powers to break down the wall and she and Emma find an empty beach on the other side. Emma warns that it’s been 30 years and it may be too late to find Anna.

Back on Blackbeard’s ship — which we learn is actually Hook’s Jolly Roger — Hans and his brothers tie Anna and Kristoff up with the intention of killing them. Anna offers to pay off Blackbeard for the “wishing star” again, but Hans says that he is now in control of all the royal money. Anna and Kristoff are put in a trunk to be thrown in the sea, but before it closes, Hans lets it slip that Arendelle was frozen for 30 years, meaning that this is all happening in the present day. He then closes the trunk and throws it overboard.

Emma and Elsa walk along the beach as Elsa swears that Anna is still alive. But at that moment, the light from her necklace goes out.

At the bottom of the ocean, Kristoff is able to untie the ropes behind his back and then untie Anna’s, but the trunk is quickly filling up with water. Anna starts saying her vows to Kristoff, but he cuts her off, saying that she doesn’t get to marry him unless they get out of the trunk.

Still standing on the beach, Elsa clutches the necklace, wishing that she and Anna were together. As it turns out, Anna’s necklace was her parents’ wishing star and Elsa’s wish is granted. The light in the necklace comes back on, the trunk pops out of the ocean before her and Anna and Elsa are reunited.

The reunion is cut short because they have to rush Anna to Granny’s. Unfortunately, Hook gets there first with the Sorcerer’s hat and captures all the fairies. Emma assumes the Snow Queen did it and admits that they’re out of options to stop the curse.

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Hook gives Rumpelstiltskin the hat and asks if they’re done with their deal. Rumpelstiltskin says that their deal won’t be done until the next day…when Hook is dead.

Emma, Elsa, Anna and Kristoff go to the Sheriff’s station to find David, Mary Margaret and the baby. They tell Emma that she has to take the baby and lock them up in separate cells while she works on breaking the curse. They tell her that they don’t fear her magic and they know that she and Elsa will use their powers to save them.

Hook comes in and asks to talk to Emma. They say goodbye before the curse hits and share a kiss—though only Hook knows that it could be their last.

Regina locks Henry in the Mayor’s office to protect him and goes to lock herself in her vault. She says goodbye to Robin and he offers to come with her. She refuses and says she needs to lock herself in her vault, not to keep people out, but to keep her in. He says that he’s not afraid of her, but she warns that he should be.

The curse spreads throughout the town and the episode ends with Mary Margaret and David — who were holding hands — letting go of each other, a look of disdain in both of their eyes.

Catch “Once Upon A Time” Sundays at 8/7c on ABC.

Reach Staff Reporter Alex Reed here.