Sterling (Ricardo Frederick Evans) and Wolf (KenYatta Rogers) in Round House Theatre’s production of “Two Trains Running.” (Danisha Crosby)

In 1969, August Wilson, who would become the most accomplished and historically ambitious black playwright this country has produced, turned 24. Did he shortchange the cauldron of late 1960s racial unrest in his aggressively talky, disarmingly entertaining “Two Trains Running”?

Not a bit. The play, which ran on Broadway in 1992, is a steadily hissing fuse, with the denizens of a run-down Pittsburgh diner slowly coming to a kind of activist consciousness as injustices pile up and spur resistance, even though it’s not a place where people are conspicuously raising fists in solidarity with the Black Panthers. The derelict who keeps wandering in bellowing, “He gonna give me my ham!” because a white man didn’t pay what he promised — he’s unhinged, but he’s not crazy. He’s Wilson’s visionary, a martyr more real than Malcolm X being memorialized a few blocks away.

Director Timothy Douglas’s new production at Round House Theatre doesn’t make this any clearer than it’s always been. If anything, it occasionally falls into the trap of punching up the comedy and broad strokes of character that sometimes make Wilson’s play seem more politically innocent than it is.

Even so, this “Two Trains” is a frequently powerful rumble through the discontented lives of underclass blacks scrambling for a toehold in a blatantly hostile landscape. The setting is a downtown diner owned by Memphis Lee, who wants a fair price for his property from a city that holds the trump card of eminent domain. The diner, a patchwork of tile and linoleum in Tony Cisek’s wonderfully scruffy set, is a headquarters for a juicy gallery of neighborhood characters: a numbers runner, a young ex-con and a booth philosopher, among others.

“Two Trains” was written in the middle of Wilson’s “decades cycle,” after successes that included “Fences” and “The Piano Lesson.” The drama surges with confidence even as it appears to drift through big, breezy speeches capped by punch lines or fueled by rage.

What do Wilson’s people talk about? Unemployment. Guns. (Can’t get a job? Might need a gun.) Death: The local undertaker, West, is burying a popular local prophet. Romance: Memphis has one employee, a young waitress named Risa, but she’s so wary of masculine attention that she has scarred her legs.

Memphis has a long memory of fleeing north from Mississippi, where he has unfinished business he aims to settle someday. Holloway, the philosopher, is a geyser of social theories and colorful anecdotes, and he’s an evangelist for the 322-year-old sage down the street, Aunt Esther.

The blatant folklore of Aunt Esther is Wilson’s way of pushing mysticism and heavy history onto the stage. He tosses a lot into the pot, but he’s also always trying to make sense of the moment. No matter how windy the talk, you find yourself leaning in as he weaves his tapestry together.

The curt practicality of Memphis, played with combustible impatience by Jefferson A. Russell, sounds like the same song in another key as the battle cry of Hambone, the shell-shocked derelict given wonderful shades of fury and fragility by Frank Britton. The hyper-earnest dreams of the ex-con Sterling, who shines with bright simplicity in Ricardo Frederick Evans’s bracing performance, rush up against Risa’s hard shell, an alluring defensiveness that Shannon Dorsey gets exactly right.

There’s a little more charisma than danger in KenYatta Rogers’s turn as the numbers runner Wolf, and Michael Anthony Williams may be a degree too amusing as the wise man Holloway — but only a degree. These are characters, along with Doug Brown’s above-it-all West, whom you can sink in with for three hours — and yes, that’s the running time for this trip. Slow spots are rare; it’s a lively, probing show, chugging toward something that wouldn’t matter as much if Wilson’s cocky script was cut, or was more rigidly logical, or was more conventionally laced with upfront plot. It’s an epic protest poem, a show worth catching whether you’re new to the Wilson experience or a seasoned fan ripe for a fresh jolt.

Two Trains Running

By August Wilson. Directed by Timothy Douglas. Costumes, Reggie Ray; lights, Dan Covey; sound design/composer, Matthew M. Nielson. About three hours. Through May 4 at Round House Theatre, 4545 East-West Highway, Bethesda. Tickets $10-$50. Call 240-644-1100 or visit .