A new promotional poster for the upcoming second half of Once Upon a Time's fifth season has been released, featuring a tease of a fiery Hook (Colin O'Donoghue).

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The poster features a giant close-up of Hook giving an ominous look as flames rise from below. This hints at Hook's presence in the Underworld, where he went after sacrificing himself for the good of Storybrooke during the midseason finale.

Once Upon a Time co-creator Adam Horowitz spoke with The Hollywood Reporter recently and teased, "I would say [Hook has] gone through a lot, as has Emma [Jennifer Morrison], as have all of them, so no one's the same."

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The Underworld will bring up a lot of emotions for not just Emma, but many of our favorite characters.

"It's going to be a bunch of things. It's not just about finding Hook, it's about what happens when Emma and all of our characters enter this realm and have to face things both from their past and present," Horowitz said. "It will hopefully be an exploration of our characters and how they react to facing things you never thought you were going to face."

As for whether people can permanently die and/or come back from the Underworld, Horowitz teased that the rules of the Underworld will ultimately be explained in the second half of the season. So fans will just have to wait and see.

Once Upon a Time returns on Sunday, March 6 at 8 p.m. ET/PT on ABC.

Tags: Once Upon A Time television ABC