LANA PARRILLA, JENNIFER MORRISON" data-credit="Jack Rowand via Getty Images" src="http://o.aolcdn.com/dims-shared/dims3/GLOB/crop/3000x1590+0+153/resize/660x350!/format/jpg/quality/85/http://o.aolcdn.com/hss/storage/midas/7acde5081bf15536c4fad0d7ea103bf7/204903446/633721068.jpg" data-mep="1554260" />While Once Upon a Time" was working on a musical episode, at the time, showrunners and ABC declined to comment. Now, though, cast and crew members have finally confirmed that the event is indeed happening, and is slated to air sometime later this season.

The news was officially announced during an appearance by the "Once" team at the Atlanta TV Festival, which took place this past weekend at the Savannah College of Art and Design. A panel discussion featuring stars Jennifer Morrison (Emma) and Colin O'Donoghue (Hook) and show creators and executive producers Adam Horowitz and Edward Kitsis offered more details about the installment, which is set to start production soon and will feature most of the cast showing off their singing voices (and singing entirely original songs).

"We are really, really excited to do it," O'Donoghue told the crowd. "Out of any show, I think 'Once' is the type of show that you can really embrace doing a musical episode and make it as musical-esque as you can."

Morrison added that it was especially appropriate for "Once" to stage a musical episode, since "most of the cast comes from some kind of musical background." And the opportunity to take the innovative series in a new direction is also an exciting one, the actress added.

" ... [W]e've been doing this for six years now, so it's fun to have something completely new to look forward to," Morrison said.

Fans are no doubt excited, too. There's no word yet on when the episode will air. Stay tuned.

[via: TV Insider]