"Once Upon A Time" returns for its 100th episode on Sunday (March 6), and the heroes are traveling to the Underworld to save Captain Hook (Colin O'Donoghue).  In the sneak peek, the heroes are seen in what appears to be Storybrooke. However, that can't be farther from the truth.

As Emma, Mary, Regina, David, Robin, and Mr. Gold walk through the Underworld, they recognize something eerily familiar.

"How does the Underworld look like Storybrooke?" Emma asks.

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Their version of Hell, where Hades (Greg Germann) presides, is a warped version of their home. There is a Granny's, but that isn't Granny behind the counter. Instead, it is the Blind Witch. Gold replies to Emma's concern with his typical snarkiness that still educates the group about their new destination.

"Your questions are pointless," he tells the group. "All that matters are that all these people in this Underworld are dead and trapped because they have unfinished business."

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With the many villainous familiar faces set to appear, it appears that much of the "unfinished business" has to do with the group. What will become of the heroes when they are confronted with their past?

The gang spots Cruella De Vil's luxury car drive by before Emma gets extremely nervous (and rightfully so). Turns out their quest to just save Hook will come with a few hurdles.

"Once Upon A Time" returns Sunday, March 6 at 8 p.m. ET/PT.

Posted by:Mannie Holmes