“I’m to scale now, to fit your kitchen,” explains an unusually servile Kimberly Gilbert midway through Pluto, an at once cosmic and interior drama from the prolific fabulist Steve Yockey. She’s been perched on her knees beneath a large, impressively rendered cherry branch since you came in, since before the play proper had even begun, an admirable show of discipline.

The identity of her character is one of the destabilizing little—although size is relative, as she says—revelations that pervade Yockey’s eerie depiction of a morning on “a day like any other,” to light on a phrase that recurs suspiciously. You’ll need at least a fraction of Gilbert’s patience to enjoy the asymmetrical puzzle Yockey and director Michael Dove have laid out, but if you can surrender to its liberal invocation of dream logic, and beat back the urge to try to, well, solve it, the inquiry is worthwhile. A tip: Keep your program closed until after the show is over. Better yet, don’t take one until you’re on your way out.

What is immediately evident is that something is rotten in wherever-we-are. As harried Elizabeth Miller (Jennifer Mendenhall, in typically fine, unshowy form) returns from her morning grocery run, the refrigerator is vibrating like Sigourney Weaver’s in Ghostbusters and the radio keeps flicking itself on to sketchy reports of a mass shooting. The sheer familiarity of that monstrous phrase is one of the horrors Yockey has factored into his existential calculus. All we want when we hear it is for the world to snap back to its familiar mirage of peace and rationality. You can’t blame Elizabeth for trying to shut out the world.

Things seem to resume their workaday shape once Bailey (Mark Halpern), her sullen college-aged son, surfaces from his basement bedroom. Like John Bowhers’ cutaway set of the middle-class kitchen in which the entire play, more or less, takes place, their chit-chat seems perfectly ordinary; the little rivulets of information that trickle out about Elizabeth’s deceased husband feel natural. Elizabeth is relieved to see her sweet boy with his nose in his astronomy textbook but takes the book, as parents invariably shall, as an invitation to talk.

Yockey has found an ingenious way to express Elizabeth’s sympathetic but addlebrained sense of things-ain’t-what-they-used-to-be: She’s incensed to be told that Pluto—named, you may recall, for the Greek god of the underworld—has been downgraded to dwarf status since the days when she used a mnemonic device to remember the orbital sequence of the planets. “Write a strongly worded letter,” Bailey tells her.

Mendenhall and Halpern’s rapport is easy to buy. Every now and then, Gilbert is called to interject some metaphysical gibberish, as though a gust of wind had blown the tarp off of the source code of the universe and she can’t help shouting it aloud. Gilbert can do anything, and she sells it. Brynn Tucker is less confident as a volatile ex of Bailey’s. She plays her scenes in the key of shrill, and there’s a reason for that, but it doesn’t seem like the most invigorating choice available to her. David Zimmerman, who has the advantage of a late and spectacular entrance, lands closer to what he’s circling. Though he projects power and mystery, you get the sense he’s just a cog in a vast and invisible machine. (And also in a visible machine, thanks to some sly costume design by Frank Labovitz.) It’s Mendenhall and Halpern’s show, however. Their relationship is the heart of this odd thing, and even though you’ll probably guess where it’s heading, their tender, layered performances give it the force of an epiphany.