"Once Upon a Time" season finale will turn Storybrooke up on its head as the good become bad and vice versa. According to the latest spoilers, the "evil" Snow White will take down the "good" Regina.

The promo clip released by the network teases some spoilers for the two-hour finale of "Once Upon a Time" season 4.

Based on the clip, Gold will have his happy ending as he arrives in full glory as a golden knight and introduces himself to hapless citizens.

"In this sneak peek at the two-hour fanfic-gone-horribly wrong, a fur-vested Regina gets more than she bargains for when she targets the carriage of the wicked, remorseless Snow White," said TVLine.

"Stranger still, Evil Snow is accompanied by Evil Charming, with whom she shares no romantic connection. In fact, she seems to have also adopted Regina's baggage during the swap... including the dead lover," it added.

In the last episode, the Author and Gold had come to an understanding, and that's going to be bad news for Storybrooke.

The synopsis for the two-hour finale teased "Once Upon a Time" season 4 spoilers as it reads, "The Author proves to be a formidable wild card and forges an alliance with Gold. Emma, her parents, Hook and Regina scramble to stop them, but when Gold and the Author turn the tables on heroes and villains alike, the prospect of any happy outcome appears worlds away."

Meanwhile, "Henry discovers he has big shoes to fill as he steps up to save his family before the story's final page is turned. It's a race to the finish, and everything culminates with a shocking twist that will leave the residents of Storybrooke reeling."

Watch out for more spoilers for "Once Upon a Time" season 4 finale ahead of the airing date on Sunday, May 10 at 8 p.m. on ABC.