Once Upon a Time: Will Emma really go dark? 

'Once Upon a Time': Will Emma go evil?

Why did \'Once Upon a Time\' introduce three villains this time?

The Hot Seat: \'Once Upon a Time\' bosses answer burning questions

Warning: This story contains major spoilers from Sunday’s episode of

. Turn back now if you haven’t watched or face the wrath of the Chernabog.

The Queens of Darkness have come to Storybrooke—and they brought along a stowaway.

returned, it wasn’t long before Rumplestiltskin (Robert Carlyle) hatched the perfect plan to get back home. First, he had to reunite Ursula (Merrin Dungey) and Cruella de Vil (Victoria Smurfit), promising that they would finally find the Author, who could provide them with their happy endings within Storybrooke.

Meanwhile, Belle (Emilie de Ravin) found a professor to translate a spell that would release the fairies from the Sorcerer’s hat, but it came at a price after Regina (Lana Parrilla) accidentally released the

villain Chernobog, which seeks out the person whose heart has the most potential to do evil. Surprisingly, however, the monster wasn’t hunting down Regina, as suspected, but Emma (Jennifer Morrison). In another twist, the professor was actually Rumple, who set the events in motion so Cruella and Ursula could provide the solution to getting rid of the Chernobog and be allowed to come to Storybrooke.

But not everyone was ready to welcome the supposedly reformed villains, as we learn that Snow White (Ginnifer Goodwin) and Charming (Josh Dallas) have been keeping a terrible secret from their daughter: She has the potential to turn bad—though that’s not all their hiding. “For Emma right now, the two people she trusts most in her life are lying to her and she’s suppressing that, so finding that out will be kind of a bummer,” executive producer Edward Kitsis says. “Emma is going to have to confront her past in a lot of different ways.”

As for whether Emma could really be corrupted, Kitsis says they plan to explore what makes a villain and what makes a hero. “If you’ve done a bad thing, can you come back from it?,” he says. “Can you become the person you want to be even if you didn’t start out that way and vice versa?”

Though their quest for the Author brought the Queens of Darkness to Storybrooke, it might be a while before Rumple and the trio of evil find their prey as we also learned that the Author and the Sorcerer are not the same person—which begs the question of why the Sorcerer had the Author’s blank storybooks. Could he be holding the Author hostage? “It kind of feels that way,” Kitsis says. “In the second half, that question will be answered, as well as we’ll meet the Author.”

One thing we will find out soon is why Ursula and Cruella, who will next set their sights on reuniting with Maleficent (Kristen Bauer van Straten), didn’t end up in Storybrooke in the first place. “That will speak to why these three, how they’re all connected and what they’re all after,” executive producer Adam Horowitz says.

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