They’re not selling cannabis edibles at the concession stand for “Constance in the Darkness: A Musical in Miniature.” But maybe they should be?

A fractured fairy tale whose trippy scenes sometimes seem to be out of order, “Constance in the Darkness” is an original musical by Michael Sommers and Josef Evans. The title character (played by Emily Zimmer) is a stargazer who falls down a rabbit hole that might be near the one that guided Alice into Wonderland.

Constance encounters a madcap fairy godmother (Maren Ward) and an evil queen (also Ward) and reminisces about her ailing mother (Ward again), while coping with various sprites and woodland creatures. Along the way, she also explicitly rejects marriage, pastel gowns and all the other tropes of Disney princess movies. (“I don’t need a fairy godmother. I can find my own way.”)

Ward, who has some of Catherine O’Hara’s daffy gravity, is the best thing in “Constance.” With quick costume changes and lightning shifts from broad comedy (there are a lot of poop jokes) to the tragedy of the musical’s final scenes, Ward’s roles are fairly small but the overall task is huge. To add an extra degree of difficulty, some of her characters are meant to be aware of the audience and some aren’t, which can’t be an easy thing for a performer to negotiate. But Ward always feels in control.

The same cannot be said for the rest of the ambitious but unwieldy show. Evans’ songs are tuneful and fun, simultaneously nodding to the familiar songcraft of Disney musicals while also being odder and more interesting. And there are flashes of cleverness in the shaggy script, such as the godmother’s list of shades of white in which a wedding gown is available, a whitelist that includes not just the expected “ivory” but also “NPR” and “Coldplay.” Unfortunately, the good moments don’t cohere into a satisfying show.

“Constance” begins with two separate prologues, an early sign that there’s a lot going on and that cohesion might not be a priority. The opening scene makes elliptical references to the relationship between Constance and her mother, but then the show seems to forget about them for periods of time as it pursues diversions that don’t add much to the main story line(s).

A highlight of the show, for instance, is Jay Owen Eisenberg, bringing lounge-act realness to a scene in which his character, a villainous lamb, croons “Jam! (A Musical Jam).” Somehow, Eisenberg manages to make that number both sleazy and charming. But, placed near the climax of “Constance,” the number doesn’t advance the piece and, in fact, mostly serves to amplify the sense of what-the-heck-is-going-on-here?