ABC’s “Once Upon A Time” returned last night, not wasting any time delivering on their promise to bring Disney’s “Frozen” to Storybrooke.

The episode begins as Anna and Elsa’s parents’ ship gets caught in a storm. As their ship is going down, their mother is determined to write a message in a bottle to the girls because they “must know the truth.”

Fast forward  5 years (and a hugely successful movie) later, Anna and Elsa are laying flowers at their parents’ graves in Arendelle as Elsa tells Anna how proud they would have been of her. Anna insists they would’ve been proud of both of them. Elsa then tells Anna that she has a wedding surprise for her.

Shifting to the present day in our world, Elsa has arrived in Storybrooke, looking equally confused and angry. Given her track record, that can’t be good.

Picking up right where last season left off, the episode jumps to Regina storming out of Granny’s after finding out that Emma brought back Robin Hood’s wife, Marian, from the past then saving her from her fated death (by Regina). Though Emma didn’t intent to hurt her, Regina has, yet again, “felt the brunt of heroism.” Robin later comes outside because he wants Regina and Marian to meet, but Marian only knows Regina as the Evil Queen and she is appalled that Robin cares for her. Regina walks away, leaving the rest of the gang worried that she’ll return to her old ways.

Sleepy and Grumpy are the first to meet Storybrooke’s latest visitor as they’re driving down a road, and Sleepy (true to his name) falls asleep at the wheel. They swerve and almost hit Elsa as she’s walking into town, but she freezes them in their tracks.

Elsa continues her walk into town, leaving frozen patches in her wake, until she sees a wedding dress in a shop window and she is reminded of an earlier moment. Elsa’s wedding surprise for Anna? Their mother’s wedding dress. Though Anna is hesitant to wear it, Elsa insists and adds “something new” in the form of a snowflake necklace. While the girls are joking about Elsa walking down the aisle with Sven the reindeer, Elsa finds her mother’s diary and she draws the conclusion that it’s her fault their parents died.

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Back in the present, Rumpelstiltskin visits Neal’s grave. He feels guilty for deceiving his new wife, Belle, who thinks she has the real dagger of the Dark One, but he admits that he only kept it to avenge Neal’s death. From now on, he plans to be the man that Neal died for, letting his “heroism show [him] the way.”

Robin visits Regina to apologize for the confrontation with Marian, which confuses Regina because she agrees with Marian’s perception of her as a “monster.” Robin assures her that the woman he knows is the farthest thing from a monster and that he doesn’t hold her past against her because he too has changed. He then tells her that while their feelings for each other are real, Marian is his wife, to whom he made lifelong vows and he has to honor them. After he leaves, Regina’s anger causes the mirror behind her to shatter. As she picks up a shard of glass, looking into it, she’s reminded of something she has been missing.

Regina then goes to the mental hospital where she's been holding Sidney Glass prisoner (for 2 seasons). She informs him that there is someone in the way of her own happiness and she needs his help to get rid of her.

After leaving the graveyard, newlyweds Belle and Rumpelstiltskin decide to spend their honeymoon in an unclaimed house that came over from the most recent curse. Determined to be a better man, Rumpelstiltskin finally gives Belle the real dagger of the Dark One. At that point, he also notices a small box with stars on it and he seems intrigued. After moment passes, he and Belle share their first dance, reenacting “Beauty and the Beast.”

While Mary Margaret, David, Henry and Emma walk baby Neal through town, Emma and Henry take turns trying to get in touch with Regina. When Henry walks off for a moment, a conversation with Mary Margaret makes it clear that Emma is avoiding telling Henry about her and Hook’s budding relationship. Hook shows up a moment later and it also becomes clear that Emma is avoiding him.

When Hook asks her about it, they’re interrupted by Grumpy running by as he announces that the town is under attack by someone wielding a lot of power, enough to freeze the ground in front of them.

In another flashback, Elsa shares the content of the diary with Anna, wracked with guilt because her parents were not on a “diplomatic trip” as they had said before they died. Instead, they were trying to find a way to curb Elsa’s power because they were afraid. Anna still isn’t convinced that it’s Elsa’s fault and takes her to her future in-laws, the trolls, to prove it.

As Hook and Emma pursue the source of the icy streets, Elsa panics and summons an enormous snow monster, similar to the one in “Frozen,” to which Hook responds, “Well, that’s a new one.”

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Back in Arendelle, Anna and Elsa visit the trolls, where they learn that their parents were on their way to a place called Mist Haven. Since Elsa can’t abandon her duties as Queen, Anna decides to go against Elsa’s wishes.

While Hook and Emma run from the snow monster, Elsa continues to hide. She also finds a newspaper with Belle and Rumpelstiltskin on the cover and a look of recognition appears on her face.

Meanwhile, Regina and Sidney are back to their scheming ways. Regina has Henry’s storybook and she explains that everything that appears in the book becomes immutable, evident by Emma and Hook’s trip to the past and the changes the book incurred. She then reveals that she wants to go back in time to when she first met Robin’s wife and kill her. Back inside the mirror, Sidney shows her their first confrontation. Regina, the Evil Queen then, had captured Marian for withholding information about Snow White’s whereabouts and Marian claims that if she had love and family, she’d know that what she’s doing is wrong.

The snow monster continues to move through town while Elsa has another flashback. Fans get their first look at Kristoff (and Sven) as he distracts Elsa, buying time for Anna on her way to Mist Haven.

The monster winds up in the forest where David, Emma and the rest of the gang try to stop it, making it angrier in the process. Everyone except Marian has been knocked out when Regina arrives and realizes that she has a choice to make. She ends up destroying the monster, saving Marian’s life. Marian admits that Regina may not be a monster after all. She welcomes Marian to Storybrooke and then leaves quickly.

After battling the snow monster, Emma and Hook talk about why she’s been avoiding him. She says that she feels guilty about ruining Regina’s happiness, but Hook knows that there’s more to it. Not ready to open herself up to him yet, she kisses him and tells him to be patient. As Emma walks away, he says that he has all the time in the world, “unless a monster comes and kills [him].”

Emma then goes to Regina’s office, but she won’t open the door. Through the door, reminiscent of Anna and Elsa in "Frozen," Emma tells Regina that she has to fight for her happiness. When that gets no response, Emma says that Henry brought her to Storybrooke to bring back the happy endings and she won’t stop until that happens for everyone, including Regina.

Emma’s speech seemed to strike a chord because Regina tells Sidney that she now wants to change fate. As she looks at Henry’s book, she says that the writer is only seeing one side of the story. “It’s time for villains to get their happy endings,” she says.

Though Rumpelstiltskin makes progress by finally giving Belle the dagger, he seems to take a step back later in the episode as he uses the dagger to open the box with stars, and conjure what appears to be the hat from “Fantasia.”

Elsa, still on the run from the rest of Storybrooke, breaks into Rumpelstiltskin’s shop. As it turns out, the photo of him and Belle on the cover of the newspaper showed the snowflake-necklace Elsa gave Anna earlier in the episode. Elsa steals it back, but the question of how it got there in the first place remains.

Back to Arendelle once more, Elsa was too late to stop Anna from going to Mist Haven. Kristoff assures her that there’s nothing to worry about and that they should both believe in her. He also reveals that Mist Haven goes by another name to its inhabitants: The Enchanted Forest.

The episode ends in the present, with Elsa holding up the necklace, vowing to find Anna.

Catch "Once Upon a Time" Sundays at 8/7c on ABC.

Reach Staff Reporter Alex Reed here.