HOUSTON — “The past is never dead,” William Faulkner famously wrote. “It’s not even past.”

The applicability of Faulkner’s truism is vast, but never more so than in connection with the particular subjects that were so often on his mind — race, slavery, the U.S. Civil War and the deep, scarcely atonable guilt of the American South.

Those themes course through “Intelligence,” the powerful and often unpredictable new opera by San Francisco composer Jake Heggie and his longtime collaborator, librettist Gene Scheer. In its world premiere at the Houston Grand Opera on Friday, Oct. 20, this richly imagined work picked up a little-known stray thread from Civil War history and wove it into a theatrical tapestry with resonances far beyond its ostensible subject matter.

“Intelligence” is only the latest of the many operas now taking the stage that grapple with the sins of American racism, both past and present. Rhiannon Giddens and Michael Abels’ Pulitzer Prize-winning opera “Omar” is due at San Francisco Opera Nov. 5, and operas by Anthony Davis and SFJazz Executive Artistic Director Terence Blanchard have addressed various aspects of Black life.

What’s compelling about “Intelligence,” though perhaps not unique, is the way its period setting compels the listener’s attention both forward and backward in time. Yes, the creators tell us, this is a story of long ago — but look around you and ask whether its urgency has faded.

The historical nugget at the root of “Intelligence” is the true story of Mary Jane Bowser, an enslaved woman in Richmond, Va., who had learned to read and write, and Elizabeth Van Lew, the daughter of a prominent Confederate family. Working together beneath the veil of their shared invisibility, the two women were able to smuggle critical military information out of the Confederate White House and north to the Union leadership.

Yet, tales of intrigue and spycraft turn out to be a comparatively minor aspect of “Intelligence,” which is being recorded for future release on Apple Music Classical. Opera moves too slowly and on too primal an emotional level to deal with intricate plots, which is why that John Le Carré adaptation is probably never going to happen.

Instead, Heggie and Scheer focus on the characters at the heart of the drama, and on their psychological responses to the system of oppression in which they’ve grown up. Mary Jane, in a luminous and soaring performance by soprano Janai Brugger, emerged as a poignant figure caught in the vise-like grip of slavery — fully cognizant of her moral claims to equality, and reduced to concealing her intelligence in order to help further her cause.

As Elizabeth, mezzo-soprano Jamie Barton created yet another stage figure of imperious, conflicted power (there were times when the character brought to mind Fricka in Wagner’s “Ring” Cycle, whom Barton has embodied so fearlessly). The fact that Elizabeth uses her overweening brilliance for good doesn’t excuse her dominion over Mary Jane, a fact she is sometimes aware of and sometimes conveniently ignores.

And because historical crimes refuse to stay buried forever, “Intelligence” includes a third principal character, the shadowy Lucinda. Her identity is a mystery (at least at first), and mezzo-soprano J’Nai Bridges, in a performance of gleaming intensity, made it clear that she was the key to understanding everything.

On top of these, the cast includes a pair of Confederate villains (Elizabeth’s sister-in-law and her adulterous beau) as well as a pair of enslaved men competing for Mary Jane’s love. Some of these subplots weave their way compellingly into the main drama; others feel shoehorned in.

In place of a chorus, “Intelligence” deploys the eight dancers of the Brooklyn troupe Urban Bush Women, whose founder, Jawole Willa Jo Zollar, served as the production’s director. The choreography, especially during an extended Act 2 interlude accompanied by percussion only, draws an explicit connection between the enslaved Black population and their African roots — another reminder of the presentness of the past.

Nowhere is that more hauntingly inventive than in the work’s opening tableau, when Mary Jane, hanging laundry to dry, is joined by a group of dancers. The snap and flap of bed sheets in the wind turns into an ebullient rhythmic dance, as the drudgery of American labor harks back to African freedom.

Heggie’s score, ably conducted in Houston by Kwamé Ryan, is built on these dualities throughout, at times more persuasively than others. He draws repeatedly on blues tonalities, which occasionally brings the score of “Intelligence” uncomfortably close to a “Porgy and Bess” knockoff.

Yet, much of what’s most keenly alive in the opera is a tribute to Heggie’s gift for vocal writing. The main characters all emerge as vividly three-dimensional figures; even the two antagonists breathe life through their music.

To witness the way this gift has been present in Heggie’s work from the very beginning, a listener only had to witness the extraordinary production of his maiden effort, “Dead Man Walking,” that opened the season for New York’s Metropolitan Opera.

This rich moral meditation on guilt, redemption and the barbarity of the death penalty had its world premiere at San Francisco Opera in 2000, and has gone on to become the most widely produced opera of the 21st century. The Met production was beamed into movie theaters worldwide on Saturday, Oct. 21, as part of the company’s “Live in HD” simulcast series, and is scheduled for an encore showing Wednesday, Oct. 25.

It’s not to be missed. Mezzo-soprano Joyce DiDonato gives a magnificently generous and incisive performance as Sister Helen Prejean, whose memoir inspired the opera (as well as writer-director Tim Robbins’ 1995 film), and bass-baritone Ryan McKinny’s embodiment of the convicted murderer Joseph De Rocher is no less formidable.

In addition to its immediate rewards, the “Dead Man” simulcast served as yet another reminder of how capaciously and broadly opera can reach — how many new subjects it can tackle, how many hearts and minds it can touch. It’s a lesson that American opera companies, embracing repertoire beyond the tried and true, have finally begun taking to heart.

Reach Joshua Kosman: jkosman@sfchronicle.com