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Warning: This story contains major spoilers from the midseason finale of

took a shocking turn in the midseason finale when a series regular met a grim fate — but fear not, EW is here to quell your fears.

After Hook (Colin O’Donoghue) resurrected all the old Dark Ones in order to snuff out the light, a number of Storybrooke residents were marked for death, forcing Emma (Jennifer Morrison) to take drastic measures in a bid to save the town. But it was Hook who ultimately stepped up in the end. Finally choosing family over revenge, Hook decided to take on all the Darkness and sacrifice himself to save the ones he loves. That’s right, Hook’s dead, but — twist! — O’Donoghue isn’t going anywhere.

“It’s complicated, because we’re going to the Underworld for the second part of the season,” the actor tells EW. “He’s sticking around, but in a completely different way and quite shocking.”

Despite that good news, Hook’s death was still a roller coaster of emotions, especially considering that Emma was the one to drive Excalibur through him in the end. “She doesn’t have a lot of time to think about it,” Morrison says. “She’s put in a situation where she has to make a decision in the moment. After what she went through — she thought she was doing the right thing by saving his life, even though he said not to, and then she realized there were all these repercussions to it. She realized how much it hurt him that she didn’t believe him that he meant to just let him go instead of turning Dark again. When she’s faced with that same decision again, she has to make the decision she knows he would want her to make. It’s one of those heartbreaking things where the decision that represents love is actually just terrifying.”

Though their relationship has been tenuous at best this season, Hook and Emma were able to resolve their love before his death. “By the time she has to drive Excalibur through him, they have a whole exchange of him getting to a place where he’s able to overcome the Darkness within himself in that moment to admit his truth,” Morrison says. “She’s been fighting to believe that — and it’s confirmed in the way that he then says, ‘I do want to be this man and I am truly the man that I fought to be for you’ — her belief that he did still love her, that it was just the Darkness that had taken over him that was pushing him to do these things, her belief in that is confirmed in that moment.”

However, Hook’s sacrifice is in vain as Emma realizes that Gold (Robert Carlyle) deceived them all and is once again the Dark One. “It wasn’t all in vain in the sense that their love for each other is real,” Morrison notes. “Ultimately, it all comes full circle to them standing before each other knowing that their love for each other is real. But in terms of her trying to control the outcome, it is in vain. The overriding lesson is that she needs to let go and not try to control everything anymore.”

Regardless of how it went down, Hook still “feels like a hero,” O’Donoghue says. “He does it for the greater good, even though he was the architect of all the problems. He does it for love, and I think that makes him feel like he is, in some way, a hero, and proving himself to Emma and to the other people of Storybrooke.”

Now the problem lies in saving Hook from the Underworld — oh hey,

why all those familiar and long-dead characters like Cora (Barbara Hershey), Peter Pan (Robbie Kay), Cruella de Vil (Victoria Smurfit) and Milah (Rachel Shelley) are slated to return in the second half of the season!

“In the immediacy of him sacrificing himself before she knows about Gold, Emma is in a state of shock and she’s trying to figure out what to do, and doesn’t know if there is a way to get to him,” Morrison says. “The weird thing about finding out that Gold is the Dark One again is that she’s furious at him, but at the same time, she now has a way to Hook. If he were not the Dark One, she would not have a way to Hook. As much as she’s furious at him, she also is grateful in a weird way that this is giving her a second chance at saving the man that she loves.”

returns Sunday, March 6 at 8 p.m. ET on ABC. Stay tuned for much more scoop on what’s in store for the gang in the Underworld!

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