Once Upon a Time: New musical details unveiled 

‘s upcoming musical episode is going to be jam-packed.

EW can exclusively reveal that the upcoming hour will feature seven songs, including a big solo for Jennifer Morrison’s Emma Swan.

they’re singing — are still being kept under wraps. (TVLine.com reported earlier Friday that Lana Parrilla would lend her voice to the episode.) When EW hit the set of Vancouver-based series last week, the cast was gleefully trying to sort some of that info out for themselves.

“We’ll all so excited about it,” Morrison tells EW. “It’s one of those things we’ve all thought about. Most of us have musical theater backgrounds or have had singing in our lives, or music in our lives, in some way. We’ve joked about it, thought about it. We’re all just listening to each other songs now trying to work out how the songs fit together and what the storyline is.”

The musical episode is slated to air this spring. Stay tuned for more details.

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