“The words had an echo in them.” That’s music critic Greil Marcus, more than three decades after the 1975 publication of Mystery Train, writing about why he co-opted the title of Elvis Presley’s last Sun Records single. Yet it’s Marcus’ words that still echo today, mainly because the arrival of Mystery Train was akin to an explosion, the effects of which have rippled forward in time. A critical look at four rock acts — the Band, Sly Stone, Randy Newman and Elvis — Marcus’ work proved once and for all that one can write about popular music with the same sense of importance and sophistication with which one writes about high art. Indeed, rock ‘n’ roll was not just “youth culture, or counterculture, but simply … American culture.” This idea, borrowed from the Band’s Robbie Robertson, that “the land makes the music,” shone a light on what is the great and true American sound and influenced the manner in which pop culture as a whole is treated and talked about and regarded. He helped make it respectable.