Look what they done to Melanie's song Ma!
Took away her back-up band, plunked her down Monday night in the middle of the Music Hall stage with nothing but an acoustic guitar, and zap - instant minstrel.
From further down home, singers Janey and Dennis had already warmed the sparse crowd with a Bonnie and Delaney-like potion of barrelhouse boogie piano, country crooning, blues belting and ethnic folk guitar.
Then a hoard of latecomers streamed in after intermission just in time to watch a tall, coltish lass - that's the word that comes to mind - skitter onstage alone and start to sing, nervous as a new nun with that same aura of inner beauty.
And yes, Melanie weaves an occasional spiritual strand into the fabric of her lyrics - all of which are her own creation.
But mostly she sings of fundamental human dilemmas - finding oneself, losing others or meeting the overhead of success - or the elemental delight of a sympathetic ear or a mountain sunrise.
And she is a real singer, capable of generating enormous excitement just sitting, picking, patting her foot and singing. No sound mix or echo chamber required.
Strumming a pounding swinging guitar and modulating her voice from a raw blast to a fragile croak, she can be pert and cheeky; as in "Animal Crackers", hurt but defiant in "Steppin'" or lyrically touching in ballads like "Baby Day".
And she raps with her fans - and even takes requests - like the humblest troubadour.
"I met six people in Hermann Park and they didn't know who I was," she gleams. "I had the experience of being invisible today."
She shivers slightly, savouring the sensation.
A poet? "Gambling is illegal in the state of mind I'm in" she winks.
And before she's through, she does every song she knows people came to hear, "Brand New Key", "Beautiful People", "Candles In The Rain", "Peace Will Come", "Railroad", "Tuning My Guitar" .. too many to count or recall.
What will stick in the mind later, rather, is the broad display of emotional fireworks that Melanie can set off.
At one point, improvising freely on her vampish "Look What They've Done To My Song, Ma?", she at last breaks into flawless cabaret French to be absolutely sure no one misses the point.
But the only thing missed in the Music Hall Monday was Melanie when she had gone.