The ensuing Spell of Shattered Sight curse may have a huge impact on good characters like Snow (Ginnifer Goodwin) and others on the next episode of ABC's Once Upon a Time.

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Once Upon a Time co-creators Edward Kitsis and Adam Horowitz recently previewed the Snow Queen's (Elizabeth Mitchell) epic plan to ruin the residents of Storybrooke with her Spell of Shattered Sight.

"It's much more emotional and apocalyptic than the other curses on our show where we're just killing people," Kitsis revealed to TVGuide.com. "This is a rage curse - fun and scary at the same time - that can bring out the worst in everyone. If it isn't stopped, it will make our characters turn on each other in horrible ways."

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As Horowitz noted, the curse was essentially "beta-tested" in the eighth episode of the season, in which the kind-hearted Anna (Elizabeth Lail) was placed under the wicked spell. With this in mind, it can only be assumed that it will have an even greater effect on some of the show's more evil characters.

"Just imagine the curse's effect on those who we know have a dark side, like our Evil Queen [Regina, played by Lana Parrilla]."

"Even a hero like Snow White has a bit of darkness she'd never dream of acting on - but the curse will reveal it," Kitsis added.

With Emma (Jennifer Morrison) and Elsa (Georgina Haig) the only characters immune to the spell, it is ultimately on them to help protect Storybooke.

Once Upon a Time airs Sundays at 8 p.m. ET/PT on ABC.

Watch the promo for the next episode of Once Upon a Time here:

Tags: Once Upon A Time television ABC