When season five of "Once Upon a Time" premieres, viewers won't have missed any action. The show will resume where they left off during last season's finale.

The cast and crew revealed the opening scene during their Comic-Con panel last July. As Emma sacrifices herself and becomes the Dark One, she disappears into the dagger. Henry, Mary Margaret, David and Hook all try to summon her back to Storybrooke, however, they are all unsuccessful. "She's not in this world," Regina finally realizes.

It seems that Emma has disappeared into another realm, yet to be unveiled, and along the way, she's bound to meet some interesting characters.

It has been revealed during Comic-Con that a mischievous and rebellious red-haired princess will be making her "Once Upon a Time" debut.

Merida, Pixar's first Disney princess, will be joining the show this season. The Scottish princess will be brought to life by actress, Amy Manson.

Executive Producer, Adam Horowitz, describes Merida as "a spitfire like [she was in] the movie. If she's not your favorite new character this year, I wont know what to say. She's a lot of fun," he said. He also added that "Amy Manson is fantastic."

When viewers meet Merida, some time has passed since the events of the movie, "Brave."

"We're going to give you a little taste of where she's been since then, what's happened to her since the end of that movie, and then we're going to see that that somewhat crosses with out people and with our 'Once Upon a Time' mythology," Horowitz said.

Merida will be meeting Emma first, before she is introduced to the rest of the "Once Upon a Time" characters. She also meets Emma at a very tumultuous time.

Emma will be struggling with the darkness that has consumed her, and may even begin to embrace the evil inside her.

"Emma went through a lot in her life. She had a tough childhood. She's had to overcome a lot of things. She's tried to be the bigger person. Now that she's going to face the darkness, she's free of that... She's going to face the darkness in herself and figure out how to overcome it," Jennifer Morrison, who plays Emma, said.

Merida will also become good friends with someone from Storybrooke. "We've always wondered what would happen if Belle and Merida went on an adventure together. We hope you do, too, because it's coming!" Horowitz teased.

Season five's story will really focus on Emma's journey and how she deals with the darkness inside her since she assumed the role of the "Dark Swan."

The show's producers have hinted that this season will explore the world of Camelot and that the world that viewers will be introduced to is a lot different from the Camelot we've come to know.

"Camelot is going to exist in a parallel timeline; it's existed long ago, short ago, present ago and maybe in the future," Horowitz teased.

Emma will seek out sorcerer, Merlin, and he may be the only one who can save Emma from the darkness.

"Once Upon a Time" will also be introducing some iconic Camelot characters this season. Elliot Knight has been cast as Merlin, Joana Metrass as Guinevere and Andrew Jenkins as the knight Percival.

"Once Upon a Time" will also celebrate a special milestone this season. The show will soon celebrate its 100^th episode and the show will definitely prepare something special for the viewers, possibly a musical episode. "We want to make it very special, and we want the 100^th episode to be our spring premiere. We're hard at work trying to not to tell you anything," Horowitz said.

"Once Upon a Time" will return on Sept. 27, Sunday at 8 p.m. ET on ABC.