August Wilson’s “King Hedley II” is among the most difficult of the 10 plays Wilson set in Pittsburgh’s Hill District. It’s a story of Reagan-era poverty and violence that savors strongly of Greek tragedy, while dipping into Faulkner country and Biblical territory. In an interview given shortly before his death, Mr. Wilson told a reporter that “King Hedley II” was the most laborious of his plays to write.

Respect the director, then, who attempts to navigate its rocky shoals. Derrick Sanders’s flawed production, which opened Sunday at the Signature, struggles valiantly with the material, but fails to find a way to transport the characters seamlessly between play’s prosaic reality and its operatic high points.

“King Hedley II” is essentially a myth, but Mr. Sanders’s earthbound approach keeps it pinned to terra firma. The set (by David Gallo) is all hard-edged reality: decrepit brick row houses, rusty fences, and actual dirt. (The backdrop, though, meant to be an old ad painted on the side of a building, doesn’t really read.) Mr. Sanders plays ’80s pop songs during scene changes, as a grounding, if pedantic reminder that we’re in 1980s Pittsburgh. But the too lifelike set and the ’80s references are jarring distractions from a story that proceeds with the grim relentlessness of fate.

That story concerns King Hedley II (Russell Hornsby), an unemployed hustler in his 30s. King, as he is called, has come home to his wife Tonya (Cherise Booth) after seven years in prison, where he went for killing the man who carved the ugly scar on the side of his face. Tonya is pregnant, but at 35, she is already a grandmother, and she doesn’t want to “bring another life into this world that don’t respect life.” King, on the other hand, is desperate to father her child.

King’s motivations are sketched out in broad terms, but they feel strangely hollow and impersonal. It’s as if the character’s wants and actions are imposed from on high by the playwright — or at least, by the harsh God repeatedly mentioned by the neighborhood soothsayer, Stool Pigeon (a persuasive Lou Myers).

King, we are told, is driven to destructive acts by the legacy of the father he never knew. But this legacy is more abstract and archetypal than heartfelt. In the poor, segregated world of “King Hedley,” children are foreordained to repeat their parents’ mistakes.

This sense of the steady progress of fate makes the air thick with dread. King plants a packet of dime-store seeds and watches them grow, but we know there will be no blossoms. As he plots a jewelry store robbery with his old pal Mister (Curtis McClarin, in a winningly nuanced performance) and talks of buying the local video store with the proceeds, we know there is no getting ahead for King — or anyone in his station.

There are some moments of humor and camaraderie on the back stoop, especially between King’s estranged mother, Ruby (Lynda Gravatt), and Tonya, two of the women who endure in this world where men drop like flies. But mostly, this is a play of large-scale themes, enumerated in lengthy monologues.

Mr. Sanders has a regrettable tendency to stage the monologues as apostrophes, all but forgetting there is a second actor onstage. This leads to one actor pontificating, often in one spot, while the other waits around. Given the generally realistic tone, the speechifying feels highly artificial — the production doesn’t give these characters the latitude to leap from reality to the landscape of imagination.

Much of the fault, though, lies with the words on the page. In trying to split the difference between Greek tragedy and naturalistic drama, “King Hedley II” lands in an unsatisfying middle zone. The eloquent, frequently heartbreaking language of the expansive monologues is difficult to reconcile with the erstwhile banter and a complicated, web-of-lies plot (involving Ruby’s old boyfriend) worthy of a thriller. And having stuck to such a literal path, Mr. Sanders has nowhere to go in the bloody final scene, which ends up playing more like soap opera than like opera.

Yet in its best moments, “King Hedley II” can still soar. When Tonya explains why she doesn’t want to have a child, her keen description of the pointless, crushing sorrows visited on the neighborhood parents is unforgettable. When King finally speaks of his horror at killing a man, it’s as if his very soul is gasping for air. Despite its many flaws, there are audible cries from the heart in this “King Hedley II.”

Until April 15 (555 W. 42nd St., between Tenth and Eleventh avenues, 212-244-7529).