The search for Hook continues on Once Upon a Time Season 5 Episode 14 this Sunday.

However, one of the big challenges will whether Hook will do what Hades wants and actually kill one of his friends.

Also, will Gold be the one to help Emma, Regina, Henry, Robin, Charming and Snow bring him back?

I was on the Vancouver set during filming of this installment and talked with Jennifer Morrison (Emma) and Colin O'Donoghue (Hook) to get some insight into what each of them are going through in this journey to the Underworld.

"They feel like a family that’s gone down there together to get a family member back. It really does feel that way," Morrison told me about the team assembled to bring Hook back to the living.

Morrison added that she's not leaning on just one person on this journey:

"It really does feel like there’s moments where she’s teamed with Charming, and Snow and then times where she and Regina are doing stuff together. It really feels like a team."

For O'Donoghue, Hook is going through a lot in the Underworld.

"He’s just physically, emotionally, he’s just a wreck," the actor said. "He’s tired, he’s been constantly tortured in the underworld so he’s a bit of a wreck."

Meanwhile, someone from his (and Rumple's) past is also in the Underworld: "Milah is here so it’s interesting to see what happens with Milah and Rumple."

In the quest to the Underworld, Emma isn't the only one who's going through a great deal.

"Snow is going through her own personal growth and dealing with certain things, and that forces Charming is going through certain things," Morrison explained. "Regina [obviously went] through everything with her mother and father being down there and all the people that she has unfinished business with."

Is Hook aware that our team is trying everything they can to save him?

"He doesn’t know exactly who and he doesn’t know exactly what they are doing," O'Donoghue shared, "but he senses that somebody trying to save him but they’re in the underworld and he doesn’t know how that’s going to happen and how they could possibly do it."

Once Gold steps up to help in bringing Hook back, don't think this means Emma actually trusts him. "

I think Emma, knowing how it is to be the Dark One now, assumes that he has ulterior motives but she’s going to ride those ulterior motives to get what she wants until she has to do something else about it," Morrison said. "It’s sort of like deal with each problem as they come instead of dealing with all of them at once."

Greg Germann is clearly having a blast playing Hades with flairs of comedy and horror .... but O'Donoghue enjoyed working with him in these episodes.

"He’s incredible," he said. "[Greg] has so much playing him. It’s really, really good."

Morrison explained that having been a Dark One, Emma is at a better place with herself than ever before.

"I think she’s changed for the better in a lot of ways for being a Dark One," she said. "She’s more at peace with who she is and what she wants and being honest about it instead of feeling unworthy of having her own wants and desires."

At the end of the day, what is keeping Hook from completely giving up? The answer isn't surprising.

"It’s Emma," the Irish actor said simply. "As Hook believes, he thinks he’s in the underworld and he’s dead. That’s all he sees. After he senses that they are there, he has a glimmer of help. But it’s his love for Emma that keeps him going."

Emma also has some insight into what other villains are going through when she comes face to face with them, Morrison teased:

"I think she also has a new empathy for the people around her who have been villains at times or have done villainous things at times and I think she has a different understanding and empathy for when they come up against other villains. She sees it from a new perspective."

O'Donoghue praised the show for going to such dark places this season:

"I genuinely think this season is one of the best seasons, if not the best. Writing wise, I think it’s dark and it’s just really, really good and it’s been a great season to work on.

Of course, O'Donoghue praised his co-star for the work she's done this season.

"Look, Jen is absolutely brilliant all the time and we have a great working relationship on set and we enjoy doing our scenes together. It’s been fun playing two completely different characters trying to relate to each other in the way that old Hook and Emma related to each other but they keep missing the mark because they’re Dark Ones so it’s been interesting to see that."

Once Upon a Time Season 5 airs Sundays at 8/7c on ABC.

Jim Halterman is the West Coast Editor of TV Fanatic and the owner of JimHalterman.com. Follow him on Twitter.