Hold on tight, “Once Upon a Time” fans. Only one episode remains until the midseason finale of Season 4, and episode 11 is promising to introduce a whole new set of problems for the residents of Storybrooke.

According to the synopsis for episode 11, “Shattered Sight,” the town will slip into “a state of chaos” thanks to the Snow Queen’s (Elizabeth Mitchell) spell. As “Once Upon a Time” views know, the magic in the Shattered Sight spell has the power to turn loved ones against each other. And the episode description promises that the fairytale characters will be “at each other’s throats.”

The good news is that Emma (Jennifer Morrison) and Elsa (Georgina Haig) are immune to the spell thanks to their handy dandy yellow ribbons that the Snow Queen put on them with magic. But that doesn’t mean that they’ll be out of danger. The pair will be forced to “race against the clock to free themselves of the ribbons,” as it’s the only way to stop the curse and the Snow Queen’s evil plans.

While the two heroes embark on their journey, other characters are at risk of being destroyed. Regina’s (Lana Parrilla) plan to lock herself in her tomb will backfire, because she’ll end up in an “epic battle” with Mary Margaret (Ginnifer Goodwin). The new mom will be forced to fight Regina on her own as David (Josh Dallas) watches from the sidelines. Hook (Colin O’Donoghue) will have his own set of problems as Will Scarlet (Michael Socha) “looks to square his tab” with the pirate.

But “Once Upon a Time” fans can’t forget about Gold (Robert Carlyle). The slippery dark one will try to “leave town forever” with Belle (Emilie de Ravin) and Henry (Jared S. Gilmore). He made a deal with the Snow Queen – but will she go back on her word? Or will Emma and Elsa find a way to stop the madness before someone gets hurt? Viewers will have to wait and see!

“Once Upon a Time” Season 4, episode 11 will air on ABC on Sunday, Dec. 7, at 8 p.m. EST. Watch the promo video for “Shattered Sight” and check out the promo photos below:

Once Upon a Time Regina (Lana Parrilla) stirs up trouble in Season 4, episode 11 of "Once Upon a Time." Photo: ABC

Once Upon a Time Kristoff (Scott Michael Foster, center) is handcuffed while Mary Margaret (Ginnifer Goodwin, left) and David (Josh Dallas, right) remain locked up in Season 4, episode 11 of "Once Upon a Time." Photo: ABC

Once Upon a Time Anna (Elizabeth Lail, left) looks frightened as she stands next to Regina (Lana Parilla, right) in Season 4, episode 11 of "Once Upon a Time." Photo: ABC

Once Upon a Time Regina (Lana Parilla) is ready for a fight in Season 4, episode 11 of "Once Upon a Time." Photo: ABC

Once Upon a Time Regina's (Lana Parrilla) plan to lock herself in the tomb won't work in Season 4, episode 11 of "Once Upon a Time." Photo: ABC

Once Upon a Time Mary Margaret (Ginnifer Goodwin) is behind bars in Season 4, episode 11 of "Once Upon a Time." Photo: ABC

Once Upon a Time Krisoff (Scott Michael Foster) stands in front of a locked up David (Josh Dallas) in Season 4, episode 11 of "Once Upon a Time." Photo: ABC

Once Upon a Time David (Josh Dallas) must watch from behind bars as chaos takes over Storybrooke in Season 4, episode 11 of "Once Upon a Time." Photo: ABC

Once Upon a Time Regina (Lana Parrilla) looks ready for a fight while standing in front of David (Josh Dallas) in Season 4, episode 11 of "Once Upon a Time." Photo: ABC

Once Upon a Time Regina's ready for trouble in Season 4, episode 11 of "Once Upon a Time." Photo: ABC