“Ask the Street,” says Danny, a veteran Manhattan garbage hauler. “The Street shall provide.”

Danny pummels his new partner with semi-mystical sayings, advice, stories, and lousy jokes. Who is this new partner? A rookie, Marlowe, as different from him as she could be.

That’s the entire cast of The Garbologists, a quirky, likable, 90-minute two-person play by Lindsay Joelle and co-world-premiering at Philadelphia Theater Company through Dec. 5. (It’s also world-premiering at City Theatre in Pittsburgh.) Set in the world of trash hauling, The Garbologists is an energetic, intriguing way for PTC to start its 47th season – and get fulltime drama back on the boards at the Suzanne Roberts Theatre.

Steven Rishard is revelatory as Danny, outsize, fault-ridden, hilarious, defensive, and ashamed, a bully who ends up, if still a loudmouth, more vulnerable and more human. Ngozi Anyanwu is equally good as Marlowe, starting off coldly reticent and enlarging into a fuller, more thoughtful person.

Joelle is a growing name in contemporary theater, setting her plays in cultural microclimates such as, well, trash collection. Garbologists has been in development a while. Joelle worked on it while a writer-in-residence with the Curious Theatre in Denver and as a 2018 class member at Philly’s famed PlayPenn. Garbologists got an honorable mention in the 2019 Kilroys List for un- or underproduced plays.

The play is based on Joelle’s interviews with garbage folks, riding along and learning about this world and its ways. And learning is a prime theme. Awkwardly, fitfully, Marlowe and Danny bridge gaps of class, gender, race, and experience to make their worlds available to each other.

Along with Marlowe, we learn trash hauler’s argot. To “mongo” is to find and keep valuables found in the garbage. A “splish” is a hazardous jet of fluid that can spurt out as you’re compacting your load. “San man” is what garbage guys want to be called. To “read the bags” is to know by shape and weight what’s likely inside.

Marlowe, we learn, is a Columbia grad student. Danny says to “ask the street” – that is, trust to fortune that you’ll find something you need. Marlowe does, with surprising results. She has a lot to teach Danny, too, some of it pretty tough: “You don’t have to give people things to make people like you. … You just got to be better.” Above all, “You don’t know me, you don’t know my life.” Each must master the art of knowing the other.

Applause for Estefanía Fadul’s knowing direction — and to Christopher Ash’s wondrous stage set, a scaffold-city of garbage that doubles as brownstone or courtroom or garbage truck hopper. And Alyssandra Docherty’s clever lighting gives us light shows between acts.

Exiting playgoers were saying, “I never knew about any of this stuff.” And that glimpse into an unknown world (one we see every day) is part of the charm. “This city thinks we’re invisible,” says Danny in a high point. “People put their crap out on the curb and think it’s gone. They think the Garbage Fairies take it away in the middle of the night.” In learning our way through this delightful dramedy, we all become students of garbage. We become garbologists.

Through Dec. 5 at Philadelphia Theatre Company, 480 S. Broad St. Tickets: $45-$55. Information: 215-985-0420, philadelphiatheatrecompany.org.