Roenia Thompson, from left, Regina Hearne, Timothy Eric and Candice D Meza in Blues in the Night Photo: Gary Fountain

As a cabaret revue that exists primarily to sell its songs, the Ensemble Theatre’s Blues in the Night boasts two key strengths that carry the evening:

Most of the songs are excellent.

And most of the renditions by the four-person cast — especially those by show-stealing dynamo Regina Hearne — deliver the material with energy and style.

Of several revues built around blues music, including Black and Blue and It Ain’t Nothing But the Blues, Blues in the Night is the simplest in concept and format — an advantage in some respects, a shortcoming in others.

Sheldon Epps conceived/compiled the show and directed its original production off-Broadway in 1980, then for a two-month Broadway run in 1982. Epps revised the show for a 25th anniversary San Francisco mounting, adding a few bits of narration to establish the framework; the Ensemble is doing that revised version.

The format is simplicity itself. In three rooms of a rundown Chicago hotel in the 1930s, three women sing of the ups and downs of life and (mostly) love, in numbers ranging from true blues of the early 20th century to swing-era jump blues, to Tin Pan Alley pop standards composed in blues/jazz-infused idioms.

The program identifies the trio as: The Lady from the Road, a sassy, straight-talking, big-mama ex-vaudevillian fueled by memories of past triumphs; the Woman of the World, a rueful sophisticate still entertaining romantic yearnings yet fearing she’s slipped past her prime; and the Girl with a Date, the naive young thing eagerly expecting a phone call.

We also hear from the Man in the Saloon — representing, depending on your interpretation, either all the men in the ladies’ lives or one particularly roguish gent who seems to have been triple-crossing all three.

If there’s a drawback, it’s that Blues doesn’t add much dramatic substance in the way of connections between the characters or continuity between the songs. For better or worse, the show is its song program, period.

Most of the time, that’s fine — especially when Hearne takes charge as the Lady from the Road. In truth, the show stacks the deck in her favor, as she gets the best and most varied opportunities, with more risque and comic songs, while the other ladies mostly nurse emotional wounds, until they get change-of-pace solos in Act 2.

Yet Hearne exudes That Extra Something in everything she does. Beyond her powerhouse voice with its big round tones, she displays a distinctive comic personality combining irrepressible impishness with innuendo. Early in the proceedings, she catapults the show to another level with her showstopping New Orleans Hop Scop Blues. She scores big time with all her turns, whether the rowdily raunchy Kitchen Man or her genuinely wrenching Wasted Life Blues.

Roenia Thompson brings the right regret and frayed refinement to the Woman of the World. She sings with strength and character, despite a tendency to uncertainty of pitch in a few early solos. She comes into her own, however, when she gets to cast her affectations aside with a raucous turn in Rough and Ready Man.

As the Girl with a Date, Candice D’Meza sings, acts and moves with the brightness and eagerness suitable to her “sweet young thing” role. She wises up soon enough, and credibly, leaping to another level with her big second-act turn, a propulsive, almost-out-of-control Reckless Blues.

Timothy Eric plays the Man as a sharpie with snake-hipped moves and a rascal’s manner. He romps through such turns as Lucky So and So and Baby Doll with driving force and shines in a sly When a Woman Loves a Man that subverts the song’s notion of a woman’s unswerving devotion.

Director/choreographer Patdro Harris and musical director Carlton Leake, who guided several Ensemble successes (including last year’s holiday hit Cinderella), have achieved a comparably lively, snappy, entertaining package with Blues. David Yates’ elaborately detailed hotel setting, Reggie Ray’s costumes and Eric Marsh’s lighting enhance the effect.

Blues in the Night only occasionally probes the full depth of the music it’s celebrating. It is frankly a show first and foremost about entertaining the customers — which it does. Yet when the cast blends its voices in an especially fine arrangement of the Harold Arlen-Johnny Mercer standard that gives the revue its title, it does convince you that (as the director observes in his program) “the blues is therapy.”

BLUES IN THE NIGHT
7:30 p.m. Thursdays
8 p.m. Fridays
2 and 8 p.m. Saturdays
3 p.m. Sundays
Through July 24
Ensemble Theatre
3535 Main
$20-$45
713-520-0055