Break out the medieval wear, polish the swords and ready the horses -- because “Once Upon a Time” is back on ABC! Season 5 of the fairytale drama kicked off Sunday night, reuniting fans with Emma (Jennifer Morrison) and the rest of the Storybrooke gang. However, the group doesn’t stay in the quiet Maine town for long in episode 1.

The premiere starts with a flashback to Minneapolis in 1989 when Emma was just a child. She was in the movies to watch Disney’s “The Sword in the Stone” when an employee of the theater approached her. Emma thought that she had been caught stealing a chocolate bar out of someone’s pocket, but the man actually gave her a warning about her future. “Leave the sword alone,” he told her, hinting that one day she would have the power to remove Excalibur. He disappeared before she could question him further.

Cut to the Enchanted Forest, and the sword is still stuck in the stone -- but not for long. Lancelot (Sinqua Walls), Sir Percival (Andrew Jenkins) and Arthur (Liam Garrigan) follow a prophecy from Merlin leading them to the stone. According to the prophecy, Arthur will use that sword to become king of Camelot. However, another knight is already there when they arrive. He wants the kingdom for his own. However, the sword does not allow it. Not only is the knight unable to pull the blade from the rock, but he turns into dust.

OUAT 1 Arthur (Liam Garrigan, center) succeeds in pulling the sword from the stone, just like the prophecy predicted in the "Once Upon a Time" Season 5 premiere. Photo: ABC

Fortunately, Arthur does not face the same fate. Just like the prophecy said, he pulls the sword from the stone, becoming King Arthur of Camelot. But of course there is a catch. The Excalibur blade is broken, and King Arthur must make it whole. It’s a little trickier than just bringing it to a blacksmith; the remaining piece of the sword is actually the Dark One’s dagger.

Speaking of the Dark One, Emma shows up in the Enchanted Forest through a portal in the ground. And she’s not alone. Rumpelstiltskin (Robert Carlyle) is with her -- kind of. When “Once Upon a Time” viewers last left off, Rumpelstiltskin was stuck in a coma, and he still is. Emma’s vision of Rumpelstiltskin is actually a manifestation of the darkness. Like the opposite of Jiminy Cricket, Rumpelstiltskin is there to make sure that Emma lets the darkness consume her. However, Emma insists that she’s going to find Merlin before she turns evil.

Meanwhile, in Storybrooke, the whole gang is arguing about whether Emma is now good or evil. No matter what she may be, they all agree that they must rescue her -- but how? The first step is figuring out where she went.

Hook (Colin O’Donoghue) decides to take the dagger and command her to return. But when Emma doesn’t reappear, Regina (Lana Parrilla) breaks the bad news to him -- Emma’s not in this world. Fortunately they have someone who knows about Merlin and the Dark One -- the Apprentice. The Apprentice tells them that Emma is in the Enchanted Forest, but he is too weak to bring them there. However, he offers a solution -- a wand that has the power to transport them. Of course there is a catch. It will work only for someone who has the light and the dark in them. Cue Regina, except she’s gone “soft” to be considered “dark” anymore. So who has the power to take them to the Enchanted Forest? Zelena (Rebecca Mader)!

The group of heroes visits Zelena, who has a band on her arm preventing her from using magic. She wants to “help,” but Regina will not risk removing the band from her arm. Hook hatches up another plan and asks Henry (Jared S. Gilmore) to use the Author’s pen to write the darkness out of Emma. But Henry breaks the news to him that he snapped the pen in half and cannot change the story. Hook’s not one to give up easy, though. He asks Henry to help him break into Zelena’s cell.

Thanks to a spilled soda, the two are able to get into Zelena’s cell. Whipping out an old potion that he’s been holding on to, Hook attempts to remove Zelena’s heart to gain control over her. But the pirate wasn’t anticipating Zelena's casting a protection spell over her own heart. The spell knocks him back, giving Zelena just enough time to steal a knife from him. Without a second thought, Zelena slices off her hand to remove the band stopping her from performing magic. With the band gone, she reattaches her hand (with magic, of course) and disappears in a cloud of smoke.

Meanwhile, in the Enchanted Forest, Emma uses a little bit of darkness to find a “whisp,” a blue ball of light that can give her answers about Merlin. But before she can grab hold of the whisp, a fiery redhead -- Merida (Amy Manson) -- snatches it and takes off !

OUAT 2 Merida (Amy Manson) is introduced in the Enchanted Forest during episode 1 of "Once Upon a Time" Season 5. Photo: ABC

Emma’s not willing to let her one lead get away, and she uses her darkness to knock Merida down. But Merida’s not scared of Emma and not willing to let go of the whisp. She explains that she needs it for her family, and Emma encourages her to take the whisp and go before she caves into the darkness. Seeing good in Emma, Merida encourages her to join her on her journey to return the whisp to its home at the hill of stones. She explains that once there, the whisp will be able to help both of them.

But what does Merida need help with? She explains that her little brothers were kidnapped after the death of their father, the king. Merida, the eldest of her family, is now queen -- something that the clans do not approve of. She wants to use the whisp to find her brothers and prove to the clans that she’s the one who holds the power.

Emma appreciates Merida’s strength and determination, but her hallucination of Rumpelstiltskin is not impressed. He wants Emma to betray Merida and steal the whisp. Unfortunately for Emma, Merida overhears her talking to herself and takes off the first chance she gets. This makes Emma angry, and she uses the darkness in her to find Merida at the hill of stones.

Back in Storybrooke, Hook has to break the news to everyone that Zelena is on the loose. But Regina knows exactly where to find her crazy sister. Zelena meets the heroes in the middle of the street in Storybrooke to make a trade -- Robin Hood (Sean Maguire) for the magic wand.

Zelena explains that her baby is her future and that she doesn’t want anyone to take him from her or turn him against her. Her plan is to use the wand to create a portal to return to Oz.

Snow White (Ginnifer Goodwin) is horrified at the thought of Regina handing over their one way to the Enchanted Forest, but Regina has no choice. She makes the trade with Zelena, and the evil witch opens the portal.

However, Regina is smarter than Zelena. As soon as her sister opens the portal, she once again latches the magic band onto her arm, preventing her from casting any more spells. With Emma’s baby blanket in her hand, Regina rounds everyone up at Granny’s (Beverley Elliot) restaurant. The whole group prepares to be sucked into the portal to the enchanted forest when Leroy (Lee Arenberg) busts in with a couple of the other Seven Dwarfs. After being left out of so many other adventures, Leroy is ready to join the heroes and help save the day.

As they wait to travel through the portal, Emma faces off against Merida. The redhead queen fires off arrows at Emma, but Emma catches every single one. Although Emma doesn’t want to kill Merida, the darkness convinces her otherwise. She uses the magic to draw Merida to her and rip out her heart. She’s about to crush it when Hook arrives with the others.

“Swan, don’t!” he tells her, spotting the crime she’s about to commit. The arrival of her friends and family makes her stall, but the darkness is still trying to control her. Snow wants to use the dagger to force Emma to stop, but Hook tells her that it needs to be Emma’s decision.

OUAT 3 Rumpelstiltskin (Robert Carlyle) does his best to push Emma (Jennifer Morrison) to the darkness in the "Once Upon a Time" Season 5 premiere. Photo: ABC

“If I don’t find Merlin, the Dark One will destroy all of you,” she warns them. However, they know that that’s not the real Emma speaking. She’s copying whatever Rumpelstiltskin says word-for-word.

Hook encourages Emma to overcome her demons, and she ultimately pushes Merida’s heart back inside her. She falls onto Hook, hugging him as her vision of Rumpelstiltskin disappears.

Finally under control, Snow hands the dagger to Emma, encouraging her to take it. But Emma doesn’t want the power. Despite the risk of it falling into the wrong hands, Emma asks Regina to hold on to it for her because she’s the only person who will “do what no one else will willingly do” -- destroy her if she turns evil.

They take Emma back to Granny’s to show her that there is no shortage of people who want to help. And to their surprise, there are others in the Enchanted Forest who also want to aid them. King Arthur of Camelot arrives with his knights and reveals that they’ve been waiting for them to show up. It turns out that Merlin prophesized that Emma would arrive a long time ago. However, that doesn’t mean he knows where Merlin is. He explains that Emma is “destined to reunite him with us.”

The group from Storybrooke follows King Arthur and his knights to Camelot. However, “Once Upon a Time” then cuts to six weeks later. Sneezy (Gabe Khouth) and another one of the Seven Dwarfs are patrolling the town when the portal twister hits. Granny’s restaurant returns everyone to town, but the group is confused. Their memories are gone, and the last thing they remember is walking into Camelot. Sneezy explains that they have been gone for six weeks.

Everyone begins to panic when they realize that Emma is missing. However, she reappears and reassures everyone that she’s with them -- as the Dark Swan.

“You went to Camelot to get the darkness out of me,” she tells them. “And you failed.”

After turning Sneezy into stone, she warns them that there is no savior in Storybrooke anymore. Regina’s ready to take down Emma like she promised; however, she no longer has the dagger. It’s now in Emma’s hands, and the Dark Swan is ready to “punish” everyone for “what you all did to me.”