Junior Wells and John Belushi must have been grinning up from wherever they are now — mumbling and slurring with cocaine-and-Tanqueray-addled approval at “Doc” Holliday’s riffing over the keyboard — a faux Hammond B-3 setting — while belting into the mike, “Call it what you like, I call it messin’ with the kid!”

Tropical heat clamped down THEATRX (pronounced “theatrics”) as if it were the Philippines or a Chicago street corner on the eve of the summer solstice. No tobacco smoke wreathed the musicians and no hard booze informed the evening as the Backwater Blues Band shuffled through 12 bars of urban attitude.

“We hijacked a theater and turned it into a juke joint,” said Sharon Mack at the door. Mack is agent and promoter of Backwater and other acts under the managerial wing of Hot Blues Engines. “We’ve been doing this every third Friday now for three-and-a-half years at this location,” Mack adds, re: the hijacking. She is, herself, a performer working closely with B.L.U.S.D. or Blues Lovers United of San Diego. Tonight’s juke joint is at 155 East Grand Avenue in Escondido. The show almost single-handedly belies my initial impression of Escondido weekend nights as half-rolled sidewalks in a hip-hop and ’50s rock chrome-and-mag-wheeled boondock. And this blues outbreak is not as misplaced as it appears at first glance; this burg is, after all, the home of Dobro.

Onstage, the band struts through their opening, “Pick up the Phone, Simone,” an original composition by Jim Gibson (guitarist) and the late John Harris. Tom Stewart, founder of B.B.B., is on drums, and Doc’s son, Tommy Holliday, stands to his side playing a hollow-body sunburst Gibson, working articulate but tentative riffs at a bassy, low volume.

“This is the best-looking group I’ve ever seen,” Gibson schmoozes into the PA. “’Course the lights aren’t up… This is Tim.” The singer/vocalist indicates Tim Cash on bass next to him, a bearded and bespectacled member of the Bayou Brothers as well as Backwater Blues. If he looks bookish then it is a South State Street bookie he looks like beneath a chitinous green/black porkpie hat.

On “Pick up the Phone,” Gibson renders slide-work on a gray Strat, eliciting the sound of a mewling North County coyote crossed with a honeyed and crooning sidewalk lech ogling a hooker. Over the course of the evening, Gibson will coax at least three different sounds out of his guitar as if he were invoking three different voices: the coyote/skirthound, a robotic chicken clearing its throat, and a lyrical siren serenading a seaside horizon. Gibson mixes musical metaphors with more skill than I do stringing sentences.

Backwater Blues Band covered Muddy Waters, Jimmy Reed’s “Peepin’ ’n’ Hidin’”, and B.B. King’s “Every Day I Have Got the Blues,” as well as originals — some sprung on band members for the first time. The group has performed together for some 15 years and it shows. Playing at a respectful volume in the small venue, one might wish for a slight upward crank on the volume knobs, a level at which (I was assured from the opening bars on) we would be in good hands.

“A long time ago,” Sharon Mack tells me, while diplomatically soliciting a cover charge of ten dollars from seduced foot traffic along Grand, “we won’t talk about how long. As a young person, I played piano and organ in our church. I learned the blues by hearing it in gospel form. On Sunday morning, people like B.B. King and Muddy Waters would be finishing up these Saturday-night gigs at these storefronts [in Chicago], and during my rehearsal breaks I would hear the music. I couldn’t get in and I couldn’t see their faces, but my Dad would notice I was gone and he’d retrieve me by ear, drag me back to the church to play the gospel.”

Speaking of retrieving by ear, Mack would gently buttonhole an enraptured music fan wandering in and unaware of the cover. Her manner, while welcoming, engaging, was as efficacious as any Pepper’s Lounge bouncer during a Paul Butterfield engagement on Chicago’s South Side in 1962. “About three years ago,” she continued, “I had a terrible car accident and realized I really loved the music. In the course of cars spinning around, I went, ‘I love to sing and I need to hear that stuff I grew up with, that music that’s in my soul.’”

Indeed, for all the world it sounded as if that’s exactly where her voice originated as she sang a cappella her original lyric to “Get Real,” written for a man in her life. When the chills subsided, I told her, “Someone oughta be signing you…now.”