There's an earnestness to 'Once Upon a Time' (8PM ET Sunday, ABC) and while I find that quality winning, I can see how some people might be put off by not just the show's sincerity but its fanciful premise.

TV's finest dramas tend to feature modern (or modern-seeming) characters of ambiguous morality who often give in to their worst impulses. There's really not a Prince Charming in the bunch, but one of the leads of 'Once Upon a Time' is the actual Prince Charming. He's not what you'd call edgy.

In some ways, though, 'Once Upon a Time's' square-ish optimism is what sets it apart from everything else on television at the moment. Well, that, and the fact that half of it is set in a universe populated by fairy tale characters such as the Evil Queen, Snow White and Jiminy Cricket.

Toto, we're not in regular primetime any more. And that alone is reason to give this show a shot.

Near the start of the pilot, we meet Emma, a solitary young woman who is played with an engaging mixture of grit and tenacity by Jennifer Morrison. Without giving away anything too spoilery, suffice to say that a young boy, Henry (a very good Jared Gilmore) tries to convince Emma that she should try to help his hometown, Storybrooke, Maine, which he believes exists under an evil curse.

In the pilot (which is available here), we also spend time in a magical kingdom where Snow White and Prince Charming are finally tying the knot. Things go awry, not surprisingly, and what's impressive about the show, which was created by 'Lost' veterans Edward Kitsis and Adam Horowitz, is that the pilot not only gracefully sets up the connections between these two worlds, it makes it clear that the Storybrooke characters' stunted emotional lives could well be explained by the curse that Henry so fiercely believes in.

During the Great Depression, 'The Wizard of Oz' and the film versions of Dracula and Frankenstein became iconic parts of pop culture, so it's not really surprising that in these difficult economic times, television has responded with genre fare and with fantasies like 'Once Upon a Time.' Shows like 'True Blood,' 'American Horror Story' and 'The Walking Dead' serve a couple of purposes: They make our fears seem real, and in a weird way, dealable (if only unemployment could be destroyed by a well-aimed shotgun blast or stake), and they also allow us to escape into scenarios that are so nightmarish that they serve as a kind of relief (hey, as bad as we might have it, we're not living in a haunted house or being eaten by zombies/werewolves/vampires).

But if those kinds of shows dig into the darker aspects of our terrors, 'Once Upon a Time' takes the opposite tack and presents us with hopeful wish-fulfillment scenarios: If only we could experience true love, find out where we really belong or discover our full powers, all the bad stuff wouldn't be that hard to handle. It's a nice thought, and the cast of 'Once,' which includes Ginnifer Goodwin as Snow White and Josh Dallas as the Prince, generally does an very admirable job of keeping both scenarios (especially the Storybrooke one) grounded in honest emotions and aspirations. It could be that Henry is just a delusional boy, but wouldn't it be kind of cool if he wasn't?

The trouble is, 'Once' has to spend a lot of time and effort setting up and serving two realities and two different versions of a large group of characters, and that tends to keep things on a superficial level. I generally like the premise and I'm intrigued by the mythology that Kitsis are setting up, but in the first and third episodes (which is all I've seen so far), there are times when the enterprise lacks a certain heft and when the fantasy realm seems a little generic. Also, some characters, especially Lana Parrilla's Evil Queen (who is also the mayor of Storybrooke), are one-dimensional in kind of maddening ways, though Robert Carlyle makes up for that with his charismatic turn as both Rumplestiltskin and a Storybrooke resident named Mr. Gold.

Still, I'll give 'Once' credit for being a show my 9-year-old son and I can watch together without feeling that our intelligence is being insulted (the dino-topia fantasy 'Terra Nova,' on the other hand, seems to think that to make a show family-friendly, every character and plot has to be ridiculously dumbed down). As 'Lost' did, 'Once Upon a Time' wants to bring us grand romance and adventure as well as bittersweet meditations on loss and absence, and it's going to be very, very hard for the new show to do all those things well.

But if the drama builds creatively on its solid foundation and if viewers embrace its rather sweet earnestness, it could well end up in "happily ever after" territory.

Note: My interview with creators Kitsis and Horowitz is here (you can also watch the first nine minutes of the pilot on that post), and my colleague Laura Prudom interviewed the show's cast here.

Follow @MoRyan on Twitter.

Below, check out a video of Ginnifer Goodwin talking to 'Live With Regis and Kelly' about getting injured on the 'Once Upon a Time' set: