Once Upon A Time Season 4
Queen of Darkness Cruella, Maleficent and Ursella will wreck havoc in Once Upon a Time season 4 mid-season premiere.OnceUponATime/Facebook

The official synopsis for Once Upon a Time season 4 mid-season premiere has been released by ABC Network.

Episode 12 is titled, Darkness On The Edge Of Town, which will air on March 1st 2015.
The official synopsis reads as follows:

Gold reunites the queens of darkness. With Gold banished from town, the residents of Storybrooke attempt to resume their normal lives. Hook and Belle search for a way to release the fairies from the Sorcerer's hat, while Emma, Henry and Regina continue to look for clues that could lead them to the Author. But when a terrifying darkness descends on the town, Emma and Regina are forced to confront the true nature of evil. Meanwhile, in New York, Gold and Ursula enlist Cruella De Vil to join their cause

As previously reported, the spring premiere will pick up six weeks after the Shattered Sight curse.

Eddy Kitsis and Adam Horowitz teased that it is a "safe assumption" that recently-banished Rumplestilksin (Robert Carlyle) has kept busy these past six weeks by tracking down the three most wicked villains in Disney history.

Rumple and Belle in Once Upon A Time
Rumple and Belle in Once Upon A Time season 4OnceUponATime/Facebook

"This back half is a lot about what makes a hero and what makes a villain, and it's about trying to realize our happy endings," Eddy Kitsis told ET online.

Meanwhile, The Queen of Darkness, Maleficent, Ursella and Cruella, are ready to get their wicked revenge and they're teaming up to unleash a whole new chapter of hell in Storybrooke.

Finding the author's library in the winter finale was a big step towards achieving a happy ending, but there are still bumps in the road ahead.

Lana Parrilla, who plays Regina/The evil Queen in the show told Entertainment Weekly, "This is a quest that has been quite difficult for Regina. With all the research she's done thus far and Operation Mongoose, she keeps hitting dead end after dead end. She's lost some faith in ever finding this author, but she's still not going to give up."

Parilla also teased that Regina will find the author by the end of the season.

She said, "A lot of that positive reinforcement comes from Henry in being the heart of the truest believer, who keeps her afloat and keeps encouraging her to not give up. He plays a huge part in finding clues. They work together and start to find clues leading to the discovery of this author, so that will play out for the remainder of the season."

Watch the promo and promotional pictures here:

Once Upon A Time Season 4
ABC
Once Upon A Time Season 4
ABC
Once Upon A Time Season 4
ABC
Once Upon A Time Season 4
ABC
Once Upon A Time Season 4
ABC