'Once Upon a Time' Stars on Hook and Ursula's "Soul-Crushing" History 

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'Once Upon a Time' Stars on Hook and Ursula's "Soul-Crushing" History

"It\'s worse than a broken heart; it\'s devastating. And this is what created the monster that Ursula became," Merrin Dungey tells THR.

teased a tense backstory between Hook (Colin O'Donoghue) and Ursula (Merrin Dungey), and during the March 22 episode, the ABC fantasy drama will dive into what went wrong between the duo.

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. "Our [characters'] paths have crossed before when Ursula was younger. You'll get to see a younger version of [Ursula, played by Tiffany Boone]. [Hook], really broke her. It's soul-crushing. It's worse than a broken heart; it's devastating. And this is what created the monster that Ursula became. And it had to do with Poseidon (Ernie Hudson)."

Viewers will learn that Ursula was actually distraught before Hook came into her life — her father was using her for his own agenda. "Poseidon, her father, felt that humans are no good," Dungey teased. "He uses my singing to run ships into rocks, because he doesn't like the humans. And I'm tired of being used."

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"There's nothing two-dimensional about these villains," she added. "To the same extent you got to see the full picture about where Maleficent was coming from, you get to see the full picture of Ursula's life. Villains aren't born, they're created. You'll get to see a lot of different colors and sides to Ursula … [and] I can say that you'll be seeing Ariel (JoAnna Garcia Swisher)."

"Hook really genuinely wanted to help young Ursula," O'Donoghue added. But as it often happens on

, a wrench was thrown into Hook's plans. "Something happens where you realize he has to make a decision. And as is often the case with Hook, he makes the decision based on his needs."

In the present, Hook approaches Ursula with a unique offer: "We realize Hook is trying to be the best man he can be for Emma (Jennifer Morrison), and so he offers Ursula a chance at her happy ending in exchange for telling him what Gold is really after," O'Donoghue teases. (Watch this clip below.)

Although it could be easy to think Hook is merely playing Ursula to (understandably) get information he needs, O'Donoghue noted Hook is sincere with his offer. "He's genuine. He wants to help her," he said. "He wants to be a better man for Emma. He's somebody who has lived for hundreds of years with revenge in his heart and hatred for Rumple (Robert Carlyle), and it's hard for him to let go of that darkness. He's slipped up a little bit in the past, even though he's trying to be good, but in this, he's genuine, he wants to help … [though] when he genuinely offers to help Ursula [in the present], he still makes some bad decisions. It's complicated."

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"It's an interesting dance, because we have some fantastic history," Dungey pointed out. But would Ursula betray her fellow Queens of Darkness? "When we first met the Queens of Darkness, there is that mistrust of one another, because we are all nefarious and out for our own [goals] – we had never joined forces, and were out for our own way. ... If the end game is getting your happy ending, when that carrot is dangled, it's pretty tantalizing. You never want to betray your frenemies, but when you have the opportunity to get what you want, it's a Sophie's choice."

Complicating Ursula's decision is her rising frustration with the lack of progress in trying to find the author.

"You saw what was happening in the beginning with Gold and Ursula back in her apartment [in New York]," Dungey pointed out. "She's impatient; these are ladies that can conjure up stuff five minutes ago. This is a long, slow grift he's pulling. I think that Ursula, of all of the gals, she wants action and she gets impatient pretty quickly. ... Along with the impatience of the process of getting to the end game, Ursula does not trust Regina (Lana Parrilla). She is still very unsure [of her]. … Maleficent (Kristin Bauer van Straten) has this long-standing relationship with Regina that Cruella (Victoria Smurfit) and Ursula do not have … Cruella and I do not think she's in it to win it. She's been too long in this town full of heroes."

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That mistrust of Regina has bonded Ursula with her fellow Queen of Darkness, Cruella.

"We're both on the same level on this," Dungey pointed out. "I think that's as good as it gets at this point in terms of an ally, because they're all still villains."

For Hook, meanwhile, his priority remains clear: keep Emma safe at all costs.

"That's the most important thing — trying to be there for Emma and trying to do the best he can do to keep her on the right path," O'Donoghue said. "He's definitely trying to be heroic … they're a solid team. Hook wants to find out what Gold's after, because he already knows [Gold] tried to kill Emma once. And tried to get Hook to use the heart to destroy Emma. Hook is trying to be a team player. He's obviously involved in trying to help find the author and help stop the Queens of Darkness and Rumple. He's very much a part of it all."

Now that viewers will get a glimpse into Hook's relationship with Ursula, he noted his dynamic with the other Queens of Darkness is strained in a different way. "He's on the opposite team from the Queens of Darkness, so it's very difficult dynamic," O'Donoghue said. "He's part of the heroes and trying to find a way to stop them." (And given Cruella's fairly blank slate of a history, O'Donoghue was coy about whether Hook had history with her, too, pointing out viewers will learn more about Cruella soon.)

What are you looking forward to seeing? Sound off in the comments below. 

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