Season 4 of “Once Upon a Time” is going to get … a little chilly. The synopsis for the highly anticipated upcoming season has been released online, and fans of the ABC fairytale are going to have a hard time waiting until the fall to watch the drama unfold.

According to the network, viewers can look forward to the following in Season 4:

“Master storytellers Edward Kitsis and Adam Horowits (“Lost,” “Tron:Legacy”) invite everyone to join Emma Swan, Snow White, Prince Charming, The Evil Queen, Hook and all the other resident fairy tale characters as they prepare to defend themselves against a magical force from the past that’s too dark and unpredictable even for Rumplestiltskin – The Ice Queen.”

While the synopsis doesn’t reveal much, the mention of “The Ice Queen” has fans speculating over Elizabeth Mitchell’s recent casting.

For those that missed the exciting news, Entertainment Weekly reported earlier in the week that “Lost” alum Elizabeth Mitchell would be joining the fourth season of the ABC drama. While a name and details surrounding her new character were still being kept under wraps, the site was able to tease that Mitchell’s role may be connected to “Frozen” … on the villain end. And that’s not all. Mitchell’s “Frozen” part on the show is expected to take place after the events that occurred in the 2013 Disney animated film.

But will the show choose to air a version of “Frozen’s” tale in Storybrooke? Or will they skip ahead? Fans will have to wait and see in the fall, but until then we’ve got a spoiler roundup to keep you busy. Check out the Season 4 news below:

“Frozen” Casting

“Once Upon a Time” teased the arrival of “Frozen” in the Season 3 finale, and the show recently made the exciting casting announcements. “Fringe” actress Georgina Haig will be tackling the role of Elsa, the Snow Queen (not to be confused with the Ice Queen), while newcomer Elizabeth Lail will take on the role of Anna and “Greek” heartthrob Scott Michael Foster as Kristoff. Elsa is expected to appear in nine episodes, Anna is said to be featured in six to eight episodes, and fans can see Kristoff in approximately six episodes.

Season 4 Premiere Title

Series co-creator Adam Horowitz took to Twitter earlier this week to reveal the premiere title for Season 4. The title, “A Tale of Two Sisters,” seems to hint that the show will immediately be diving into the “Frozen” storyline of Elsa and Anna.

The Arrival of “Frozen”

“Frozen” lovers know that Elsa was misunderstood, but will she be represented the same way in the ABC series? That’s the big question for Season 4. Horowitz previously told TV Line that viewers might not see Elsa and Anna happily united when the show airs – which means that “evil” Elsa could be introduced in the premiere.

Emma And Hook

Don’t expect a fairytale ending for Emma and Hook in Season 4. While the two ended Season 3 on a very good note, the couple will reportedly encounter some “challenges” when Season 4 kicks off.

“The very first obstacle is Emma’s guilt over the fact that she just destroyed Regina’s relationship [with Robin Hood],” Horowitz explained. “So there’s a part of her that feels guilt in starting a new romance of her own.”

Emma Vs. Regina

These two women will never get along. Emma’s Jennifer Morrison previously teased that the show will go to the two being adversaries … all thanks to Emma’s decision to bring back Maid Marion from the Enchanted Forest of the past.

Mirror, Mirror On The Wall

“Once Upon a Time” has been on a casting binge, but the show will also welcome back a familiar face – Giancarlo Espositio. Viewers will remember Esposito as Sidney Glass in Storybrooke, or the Magic Mirror in the Enchanted Forest. He’s been missing in action for some time, with fans last seeing his name on a locked door in the sketchy basement of the Storybrooke hospital.

Are you excited about Season 4 of "Once Upon a Time? Tweet your thoughts to @AmandaTVScoop.