You may be thinking with all the sneak peeks and song releases that you’ve basically already seen “The Song in Your Heart,” but I’m here to tell you there’s more to it than these lively ditties, which mostly take place in the past. We're going to leave it at that for now, however, because we don't want to spoil it for you! Just trust us, you've got to watch this episode.

It would appear that regardless of all the years of interest and teasing, no one really expected a Once Upon a Time musical episode. Even the actors themselves seem surprised that this episode has finally come into being. It makes sense though, as Yvette Nicole Brown has pointed out at SDCC for years, due to the amazing talents of the Once Upon a Time cast.

Jennifer Morrison (Emma Swan) comes from a very musically talented family. She has an amazing voice, as you shall hear, and admittedly loves playing the piano, though she claims she’s not good at it. In this snippet you’ll hear that her song is not just beautifully rendered, but based on Emma’s theme score composed by the marvelous Mark Isham.

The lovely Lana Parrilla (Regina Mills/Evil Queen) might claim that she can’t sing (as she did at Fairy Tales III), but that wasn't exactly true. Now that her Evil Queen rockin’ solo has come out, everyone knows!

I also love how, in the interviews above, Parrilla describes the Evil Queen’s solo as “David Bowie meets The Rocky Horror Picture Show!” See if you can hear the similarities between the guitar riffs of “Love Doesn’t Stand a Chance” and “Sweet Transvestite” for yourself.

Our very own Prince Charming (Josh Dallas) has a history on Broadway. That’s right, our main man is a triple threat! We can’t leave out his leading lady, though. Ginnifer Goodwin (Snow White) also has quite a pair of lungs. You may have heard her vocals as Judy Hopps on Zootopia. Now, you can hear the magic of their voices together.

Of course, Colin O’Donoghue (Captain Hook/Killian Jones) is already known for his singing and guitar playing. He co-founded the band The Enemies prior to his current acting gig, and used those talents in the film The Dust Storm. I suppose it’s only fair, after all these years, that he use them for Once Upon a Time too. Besides, I have to admit, O’Donoghue is really good at pulling off the flair needed for a successful musical.

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It turns out that many more of the cast members can sing and dance. You’ll be able to see vignettes by Beverly Elliott (Granny), Tony Amendola (Geppetto), Lee Arenberg (Grumpy/Leroy) in “Love Doesn’t Stand a Chance,” and a wicked solo by our one and only Wicked Witch, Rebecca Mader.

Check out this sampling of Once Upon a Time’s musically talented cast, including Parrilla, Dallas, Maguire, O’Donoghue, Goodwin, Mader and more.

Even Jared Gilmore (Henry) had a line in the culminating performance. These songs may not be the familiar Disney songs from our characters’ derivative animation films, but they are in the same vein/spirit. They have a good, yet “wacky,” way of capturing the emotion of the scene or situation whether it be anger, love, sadness, desperation, wickedness, or the overt desire to win.

There are two sides to this event: the fans who can’t wait for it to air, and the ones who can’t wait for it to be over. Which are you? Regardless, be sure to watch tonight on ABC at 8 p.m. EDT so that you can claim the merits of your opinion. Then, check back here for our review!