New pages will be turned in "Once Upon A Time" when it returns Mar. 1 with an episode titled "Darkness on the Edge of Town." Evil looms over the magical town as the Queens of Darkness prepare to cast their shadows on Storybrooke. However, the band of three deadly divas Ursula, Maleficent and Cruella De Vil may welcome a new bad girl into the scene. 

As Emma and Hook become "pretty close," co-executive producer Edward Kitsis told TV Guide that troubles will get in the way of their burgeoning romance. The former is "about to find out some really bad information" about Hook, who has a lot of things going on inside his head. But the real deal breaker here is Emma's possible shift to the dark side. 

As "Once Upon A Time" delves into the makings of a hero and a villain's mind, co-showrunner Adam Horowitz revealed that Emma is growing tired of being branded as the Savior or the hero. Add to that the feeling of being betrayed by Charming and Snow White, who have been shunning telling her about the Savior prophecy the whole time. 

"Now she's going to have to face that it's not as black and white as that. Going into the second half of the season, all of our characters are going to be wrestling with this idea of good and evil, not just in terms of what they're facing as an external threat, but internally within themselves," Horowitz shared. 

The executive producers also teased that Emma will be onboard Operation Mongoose. And as she helps the Queen in searching for The Author and even assist her on the romance side (the executive producers revealed that Robin Hood will be back and an episode centered on him is coming), media outlets believe that she will return the favor by helping Emma rise above her crisis. 

"Once Upon A Time" will be back with a vengeance, sass, magic and shocking secrets. Watch them all unfurl on March 1. The show can be watched online via livestream on ABC.