Emma (Jennifer Morrison) will go through a bunch of different emotions as she journeys into the Underworld on ABC's Once Upon a Time.

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As Once Upon a Time returns for the second half of season 5, Emma will have to grapple with saving Hook (Colin O'Donoghue) and having slight regret over bringing her family into the whole mess.

Morrison spoke with Entertainment Tonight in a new interview about Emma being even more vulnerable than before.

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"Well, now that Emma has been through that Dark Swan experience, she's sort of in a more vulnerable and open place than she's ever been in her life," Morrison said. "She's determined to save Hook and, obviously, desperate to save Hook because the stakes are very high at this point. He's actually in the Underworld, which is not a great situation."

As always, Emma will also feel the added pressure of having to worry about the various people she loves.

"Her family decides to come along with her to try and save him and that means a lot to her," she noted. "But at the same time it puts a lot of pressure and I think she has a lot of guilt about that. So she's also dealing with the burden of worrying that maybe she's done the wrong thing for her family by letting them come with her."

Yet, at the same time, Emma has been through hell and back in the past five seasons of the show so her journey to save Hook is still a somewhat confident one.

"I mean, I think there's no limits as to where she's willing to go at this point," Morrison said. "She's gone through so much to get to a place in her life where she's strong enough and vulnerable enough to love without walls up, which I think is a really brave thing."

Once Upon a Time season 5B begins Sunday at 8 p.m. ET/PT on ABC.

Tags: Once Upon A Time television ABC