Something brilliant is coming to Zach Theatre’s Whisenhunt Stage. Actually, make that a whole long list of somethings.


The intimate space will soon play host to "Every Brilliant Thing," an interactive, innovative one-person theatrical performance that finds hope in the somber topics of depression and suicide. Written by Duncan Macmillan with Jonny Donahoe, "Every Brilliant Thing" centers on a young boy’s growing list of reasons that his mother, who struggles with depression and suicidal ideation, should keep living. "As the play goes on," director Nat Miller said recently, "(the main character’s) life gets more complicated," and "the list gets more sophisticated."


Meanwhile, there is only one actor on stage. Audience members are responsible for reading off items on the list and playing various people that the main character interacts with throughout his life as he deals with the tragedy — and the brilliance — of being alive. List items like "staying up past your bedtime" and "the smell of old books" prompt vignettes that work to build out the character.


In such an intimate performance, the job of interpreting and giving life to Macmillan and Donahoe’s written words rests largely in the hands of Miller, a longtime member of the Austin theater community, and the actor playing the main role, Kriston Woodreaux.


Woodreaux, a former Austinite who moved to Los Angeles in August, says that he agreed to return to perform the play "within five minutes" of being on the phone with Miller, with whom he’d previously worked during Zach’s performance of "This Girl Laughs, This Girl Cries, This Girl Does Nothing."


The two have taken a collaborative approach to rehearsals for "Every Brilliant Thing"; Woodreaux says he even decided to change up his typical approach by not memorizing lines ahead of his first rehearsals with Miller, hoping to arrive as "a blank slate." In this way, "I've been able to really take in everything that he’s been offering."


So how does an actor prepare for a play when their primary scene partner is an audience of strangers that will change every night?


During rehearsal, "our stage manager (Michaela Langford) is generous to get up as much as she can" to fill various audience roles, Miller says with a chuckle.


But still, Woodreaux knows that essentially he’ll be creating something unique and ephemeral, something that changes every night.


He breaks down the process, gazing around the circular room, envisioning a full crowd and showcasing the range of skills that a role like this requires: "Every person that comes through, they’ll receive a program, and I will size them up and down, and I’ll be figuring out who I can use for certain things. (I’ll notice) whether someone is especially vocal when I meet them and they're really physical and they give me a hug versus shaking my hand. Those are things that I need to pick up on. Is a person wearing a certain type of clothing? Because that means I can use them for something."


(Miller knows that "audience participation can scare people off a lot" but assures potential audiences that "it’s easy, it’s gentle, it’s prompted — it’s a lot of reading things off paper.")


But in the end, Woodreaux says, his reality is "preparing as much as I can with the blueprint that I have and knowing that it could deviate from any one of those points."


And he acknowledges the possibility of chaos: "We could have someone call out a number and not say what they're supposed to say. How do we prepare for that? So it’s a script, but it’s a million scripts in one."


While many of us might consider such a situation terrifying, Woodreaux gleefully says that’s the kind of thing that makes him come alive as a performer: "That’s fun! It gives me good butterflies. I love being thrown off."


Indeed, Woodreaux seems to have been gifted with or actively cultivated a fearlessness that is perfectly suited to a show like "Every Brilliant Thing," which requires a certain bravery in the way it confronts mental health issues — a topic that is still a struggle for many people to discuss — through the mother’s depression and the main character’s own struggle to cope with and understand that experience.


Despite his family having a history of mental illness, "I don't remember at all ever talking about mental health in my family," he says. His parents didn’t even tell him about an ADD diagnosis he received as a child until he was about to drop out of college. "It feels like there's this black cloud. … That (mental health) is a stigma that folks don't like to talk about and that we would rather push off to the side."


Miller calls "Every Brilliant Thing" "a reminder that we all deal with these things, and we all need to talk about it, and we all need reminders of why it’s important to have hope."


"I know," Woodreaux says with a sense of proud responsibility, "that we’re going to have folks coming in here who are going to be speaking to us after" about the ways that mental illness has touched their lives. "And if this is the perfect arena for folks to talk about it, then that’s what we have to do."


Ultimately, Miller says, "the thing about this play is that even though it deals with heavy issues of suicide and depression, it’s also really uplifting because it’s about hope."