It seems Lynn Nottage is everywhere. Her 2003 play Intimate Apparel is playing at the McCarter Theatre in Princeton, and the powerful One More River to Cross is having its world premiere at the Latvian Society through June 11. 

A true alchemist of the stage, Nottage gathers first-hand accounts of men and women dispossessed by war and poverty and distills them into transformative dramas. In Ruined (2008), which earned her the first of two Pulitzer Prizes, she told of the lives of women affected by the civil war in the Democratic Republic of Congo. The 52-year-old Brooklyn native stayed far closer to home for Sweat (2015), an exploration of poverty based on interviews she conducted with residents of Reading.

Nottage  travels not in space but in time for One More River to Cross: A Verbatim Fugue, a testament to the effects of American slavery. The production opened Friday in Philadelphia after a preview stand in Jenkintown.

Presented for this world-premiere production by Pulley & Buttonhole Theatre Company, One More River is a free-form, open-ended tapestry of word, song, and dance based on first-person accounts that loosely follow the history of slavery in the American South. Animated by a cappella performances of Negro spirituals and gospel songs, this is a highly enjoyable if flawed production that would profit from a sharper structure and better balance between narration and song.

River juxtaposes story, song, and dance to comment on how dispossessed peoples use an oral tradition to create their own collective memory and a shared experience. Denied an education, denied the instruments and expressions used by the dominant culture to record its own evolution, slaves used unique forms of irony to modify and undercut the official language, the official songs and hymns, the official religion and art.

Nottage, who did her own reporting for Ruined and Sweat, relies here on archival material, specifically interviews of 2,300 emancipated slaves conducted in the 1930s by the Federal Writers' Project. The interviews make up one of three strands of raw material Nottage weaves together for the drama; the songs and the dance serve as illustration and counterpoint.

Four storytellers (Beatrice Alonna, Kareem "Doc" Carpenter, Kamili Feelings, and Sara Osi Scott) occupy a slightly raised dais at the back of the stage on which sit a couple of beautiful, high-backed wooden armchairs.

There is very little in the way of dialogue or interaction between the  two men and two women. Instead, they take turns delivering material from the interviews.

Surrounded on three sides by audience seats, the performance space features a larger orchestra section populated at any time by one or more of eight ensemble players – Quinton J. Alexander, Kent Darden, Jessica Heller, Adiah Hicks, Gil Johnson, Charly Sarah Klinman, Juliet Davida Klinman, and Nastassja "Baset" Whitman. A cross between a Greek chorus and a tableau vivant, they sing, chant and intone, dance, jump, fall, and pose. The choreography is simple, minimalist, though highly effective, as are the costumes and masks. Ensemble members are rarely, if ever, shown without one of a series of masks. Some are simple numbers, large pieces of painted paper; other are far more complex works of papier-mâché or carved wood.

One More River is produced and directed by Philadelphia photographer and dramatist James Jackson, whose skillful mastery of the material is evident throughout. But I wonder whether, in his bid to keep the overall movement of the play as smooth and fluid as possible, he doesn't end up sacrificing the intensity and heat of the first-person accounts.

The storytellers deliver verbatim quotes from  accounts that are roughly organized chronologically from slavery's earliest years through the Civil War. Some of the material is deeply shocking, but the performers' delivery is often upstaged, if not entirely obscured, by the remarkably lively sights and sounds of the chorus.

The production's flaws hardly detract from the effects of Nottage's work. One More River to Cross is a powerful testament about the history of slavery – and so much more.

One More River to Cross. Through June 11 from Pulley & Buttonhole Theatre Company at The Latvian Society of Philadelphia, 531 N. Seventh St. Tickets: $35. Information: 215-392-9958,