As if love in one universe isn’t complicated enough, imagine a multiverse where an infinite number of scenarios plays out in a million possible ways. Or not at all. That’s the theory behind Constellations, Nick Payne’s “time-bending romantic drama,” onstage at Santa Paula Theater Center through July 29.

Mixing romance and science, specifically theoretical physics and the relationship(s) of Roland and Marianne, Constellations plays with the idea, held by a number of rather brilliant people, that there are, as Payne explains, “an unimaginably vast ensemble of parallel universes” in which exists “every choice, every decision you’ve ever made and never made.” Put more simply by Michael Longhurst, who directed the play in New York, Constellations is a story of “Boy meets girl. Boy meets girl again. Boy meets girl again . . ..”

The “boy” and “girl” are Roland, a beekeeper, and Marianne, a theoretical physicist. We see them meet for the first time at a mutual friend’s barbecue, and then we see them meet again and again. Sometimes they hit it off. Sometimes not. What unfolds are rich little vignettes that peek into different ways their story plays out. In some they are happy. In some they almost destroy each other. In yet others, Roland and Marianne miss each other completely, like shooting stars in the night. They fall in and out of love, face illness, contemplate death and dance with time.

Jessi May Stevenson and Ron Feltner embrace Payne’s work wholeheartedly, diving into the complexity of the material without losing hold of the heart of the play: love, in all its beauty and cruelty. Their wonderful collaboration with director David Ralphe results in a mesmerizing pas de deux in which they move through scene after scene, across the universes, shifting gears in an instant, never missing a beat. Lighting design by Gary Richardson and sound design by Kevin Kahm and Alan Noel help us navigate time, space and scenario. Costume designer Barbara Pedziwiatr and prop master Gail Heck round out the talented crew.

Constellations takes place in England, so the actors adopt accents for their roles, but the varying success of the affectation is irrelevant. The language is key, not the accents, and Feltner and Stevenson nail the meaning of the words and the emotions behind them. Feltner is always fun to watch and here he imbues each version of Roland with distinct and charismatic shading. As Marianne, Stevenson shines as an icy academic in one universe, a lovable nerd in another, a devastated woman battling a debilitating illness in the next. (The scenes of Roland and Marianne confronting her diagnosis and its different outcomes are the most powerful in the play.)

In a landscape filled with musicals and comedies boasting large casts and big production numbers, Constellations is a refreshing change of pace that should not be missed. It’s just two people, a black box and a sky full of stars. We sail through the universes with them, rooting for them all the way. It doesn’t matter if you understand theoretical physics — or even love, for that matter. The premise of Constellations may be rooted in scientific theory that could make your head spin, but at its core, its power is in its simplicity.

Constellations through July 29 at Santa Paula Theater Center, 125 S. Seventh St., Santa Paula. For schedule, tickets and more information, call 805-525-4645 or visit www.santapaulatheatercenter.org.