Hell hath no fury like a Dark One scorned!

Once Upon a Time's mid-season finale is sailing our way this Sunday, and -- thanks to our double dose of Dark Ones and a mission to the underworld -- it's guaranteed to be one hell of an episode.

To get you even more pumped for all the action, we called up everyone's favorite "piercing-eyed, smoldering pirate," Colin O'Donoghue, to bring you exclusive details on Hook's transition back into a perfect-haired villain, exploring the relationship between Killian and his father, and why Emma has eclipsed Milah as the love of his life!



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We haven't talked since Comic-Con, where I realize now that Jennifer Morrison gave the biggest spoiler ever when she joked that Emma was going to "suck [Hook] into the darkness" with her. How long have you known that you were going to become a Dark One?

Colin O'Donoghue: I guess it happened! [Laughs] To be honest with you, we didn’t really know at Comic-Con. It was up in the air as to what way it could go, and with a show like this, there's so many different things that can happen with each of the characters because we’ve got 22 episodes to do. But, I think the [executive producers, Eddy Kitsis and Adam Horowitz,] like to keep big secrets like that for just before we're going to shoot the episode and then you kind of go, 'What?! Are you serious?' It was sort of a logical step for Hook in a sense. Not that he wanted this, but this is a character who already had been predisposed to the darkness and now to be able to go and delve into that is good. Also, Hook is character who kind of divides the fans in a lot of ways. I mean, some people really like him, and some people really hate him because of that very reason, and I think it was fun for me to be able to explore that side of him again.

Your portrayal as a Dark One has been so fun to watch, and fans are particularly loving your new hair. Talk to me about the process of changing your look and your demeanor to play a Dark One.

CO: Oh, thank you very much! Thank you. [Laughs] The process of changing my hair was pretty simple, it was just parted on the other side, I guess. As for the approach -- look, when I came onto this show, I was essentially a villain, and that was sort of what I spent a lot of time in season two exploring. He was a little bit more charming, and probably more of a bad boy, but definitely now, as a Dark One, he's more of a sociopath, more malevolent, and enjoying the fact that he is like that. I think deep down inside, there is a tiny, tiny little part of him that hasn't quite fully turned dark and that could still love, but he's also just incredibly, incredibly pissed off with Emma for having done the one thing that he asked her not to do. He knows that he never had the willpower to be able to fight [the darkness], and he just sort of fully gives into it. Well, he had no choice; the darkness doesn’t give you much of a choice. He never really had the opportunity to say, 'Nah, no thanks. I'll stay as the old Hook. Once he'd been changed, he'd been changed.



WATCH: Hook and Emma Can't Stop Kissing in This Sneak Peek!



ABC

You mentioned how incredibly frustrated Hook is with Emma, but she really only had two choices: Hook becomes a Dark One or Hook dies. Would Hook really have rather died than become a Dark One?

CO: Honestly, yes. I think he would have. When he was basically on his death bed he said to her, 'Let me go,' and he meant it. I think because the Dark One is the one thing he's always hated most in his life, I think that he would have definitely preferred to die. I'm glad that he didn’t because that means that I still get to be on this show, [Laughs] but I think for Hook as character, I think he really would have preferred death.

What is Dark Hook's goal as we move into this Sunday's mid-season finale?

CO: Well, we've sort of teased in the teasers for the next episode that Hook, like all Dark Ones, wants to bring the Dark Ones back and use people to open the portal back to hell, and that's what the darkness does. In doing so, that essentially would allow him to get his revenge on Rumpelstiltskin because he would be one of the people who would be sent to hell, or to the underworld. That's his overriding goal. Hook understands that the darkness is using him, but as long as he gets what he wants, then he's happy to do that.



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Do you feel like becoming a Dark One and wanting to seek revenge on Rumple has, in turn, reignited the flame that he once carried for Milah?

CO: Oh, no. Milah is sort of this whole different thing. She's a love that he had and he truly loved her, but he now has a whole different new love that is such a huge part of who he is -- and maybe even more so because they're so kindred. That's not to say that he's not incredibly annoyed with Emma, but I think deep down, as we've seen with Rumpelstiltskin and even with Emma, you can still love somebody. It's just how you treat that person is the problem when you're the Dark One.

ABC

So you're saying that no matter how annoyed Hook is with Emma right now, there's still hope for Hook and Emma to have their future together?

CO: Well, I'm not sure that I'm saying that. I'm just saying that they have the propensity to love. Maybe there is and maybe there isn't, but they are both Dark Ones, so maybe they still could love each other. Who knows? You'll have to watch and see. [Laughs]



MORE: 'Once Upon a Time' Bosses Spill on Exploring Hook's Past



Earlier this season, I chatted with Adam and Eddy and they revealed that we'll be delving deeper into Hook's past in the second half of this season. What was your reaction when you found out that was going to be happening and what can fans expect?

CO: I was delighted to get to explore more of who Hook is and where he came from because that's something that we haven't really done before. I know that we saw a little bit with Liam, but it was nice because we're going to meet Hook's father. That was a very important thing for me to get to explore because he, obviously, was such an important part of forming who Killian Jones came to be as a person. It's interesting, but I can't really tease too much about it because it's quite spoilery, but the fans should expect to see some very interesting stuff between Hook and his father.

Lastly, Colin, what is the one thing that you want Once upon a Time fans to know before they tune into this Sunday's mid-season finale?

CO: They should be prepared for a heartbreaking, heart-wrenching, huge, epic mid-season finale.

Once Upon a Time's mid-season finale airs Sunday at 8 p.m. ET/PT on ABC.



Do you think Dark Hook and Dark Emma have a chance at a happily ever after? Who else is dying to meet Hook's father? Share your thoughts with @Leanne Aguilera on Twitter!

