Eboni Booth dreamed up the story that became “Primary Trust” for a school assignment. She was a playwriting fellow at Juilliard, and she decided to write about a guy who works at a bank. At the time, she drank mai tais, and soon, so did her protagonist.

That play, which she drafted in 2019 and which was first staged last year, won the Pulitzer Prize in Drama on Monday. The judges praised it as “a simple and elegantly crafted story of an emotionally damaged man who finds a new job, new friends and a new sense of worth, illustrating how small acts of kindness can change a person’s life and enrich an entire community.”

The play, set in a fictional small town outside Rochester, N.Y., and starring William Jackson Harper (“The Good Place”), was staged Off Broadway by the nonprofit Roundabout Theater Company. The first West Coast production is scheduled for this fall at La Jolla Playhouse in San Diego.

Booth, 43, grew up in the Bronx and now lives in Queens; she had a previous play, “Paris,” staged in New York in 2020, and she has also worked as an actress. She talked about “Primary Trust” on Monday afternoon, shortly after learning that she had won the prestigious award.

These are edited excerpts from the interview.

For those of our readers who didn’t get to see it, what is “Primary Trust” about?

“Primary Trust” is about a lonely guy with an imaginary friend, and what happens when he loses his job.

You’re a city girl, but this play is firmly set in a small town in upstate New York. Why?

There’s something about the Northeast that really has captured my imagination. I really am interested in the weather, and what those towns look like, and, for “Primary Trust,” I was interested in a place where maybe its better days were behind it, so there’s this sense of loss that people have to live with all the time.

Loneliness seems to be a subject you’re interested in. Where does that come from?

I think I’m just a little mournful by nature, and a lot of my writing has been a way to understand people I’ve loved and lost, and it’s been a way to reckon with my anxiety about all that I’ll lose in the future. That sounds a little overheated, but I think it was my way of trying to understand some of my sadness and some of my hope.

You wrote this play before the pandemic, but it was staged after the pandemic, and that seemed to affect how it was received.

One of the things that people responded to is that we all felt so alone, and we all lost so much. And what is the antidote to this? I think some sense of connection [is what] we were all really craving.

The Pulitzer in drama has a preference for plays about American life. Do you think this play is distinctly American?

I think the idea of people falling between the cracks and not having a safety net … in this country, we just really let people bottom out. It feels like structurally, there’s just not enough in place so that people don’t fall by the wayside.

What did you hear from audience members after the play opened?

I wrote this play because I feel so alone so much of the time, or I have felt so alone, particularly when I was growing up. Just knowing that it resonated with people — that was it! I wrote about being hungry for connection, and then I got so much connection through the production, and that was very meaningful. I was also pregnant at the time when we were going through production, and my baby was born three weeks after we closed, so just being between worlds and being really aware of the gift of other people and thinking about the kind of parent I wanted to be and how I wanted to take care of my baby — all of those things were in my mind as we were building this world.

What’s ahead for you?

I’m not sure. You know, I have a 9-month-old, so I’m spending a lot of time with him. And I’m trying to write a new play. And I’ve been working with HBO, trying to figure out what a television show could be. And I’m working on “The Queen’s Gambit” musical with Whitney White and Mitski. And that’s kind of it for right now.