While the Marc Bolan and T. Rex catalog was basically spread over several dozen poorly annotated compilations, scarcely listenable bootlegs, and overvalued rarities, 20th Century Boy came along and, for the first time, the entire picture came blasting into perspective. Issued only in Australia but widely imported elsewhere, three vinyl albums document Bolan's entire career from 1965-1977. There were 63 tracks rounding up impossibly scarce 45s by John's Children, Tyrannosaurus Rex, Dib Cochran & the Earwigs, and Big Carrot alongside the expected T. Rex hits and album tracks. Brief interview segments close three of the six sides, and the triple-gatefold packaging features excellent liner notes and illustrations. Each side of the LPs featured at least one cut not found elsewhere. Sides one and two are the killers. Opening with ten solo sides recorded between 1965-1967, ranging from Bolan's first 45s through the demos that were eventually compiled for Beginning of Doves, the image of the singer as a Donovan-capped neo-folky is so pervasive that the arrival of John's Children material at the end of side one is as shocking to the listener as it must have been for Bolan's original fans. For many collectors, 20th Century Boy offered their first opportunity to hear what the fuss was all about.
Side two is a straightforward best-of assemblage, dignified by a handful of single-only tracks; side three completes the survey of Bolan's pre-fame meanderings with "Oh Baby," cut under the Dib Cochran pseudonym with a lineup once believed to include David Bowie on saxophone (this has now been disproved, although Bowie's lieutenant, Mick Ronson, was in attendance), but that doesn't detract from a glorious knockabout performance. The glory years consume the remainder of this second LP, with the next major rarity wrapping up side four with Bolan's Christmas messages dispatched to his fan club in December 1973. Obviously, then, the rest of the collection is concerned with Bolan's so-called declining years and his rebirth in 1977. Side five, however, kicks off with "Squint Eye Mangle," a funky instrumental cut under the Big Carrot alias and released to little notice in 1973, while side six resuscitates a few non-LP B-sides.