In 1957, Elvis Presley was the epitome of cool. But what a difference a decade makes. By the Summer of Love, the still-pompadoured singer was - at the ripe old age of 32 - a musical anachronism in a year that brought the Doors, Jefferson Airplane, Monterey Pop and Sgt. Pepper's. Plus, he'd been churning out shitty movies with lame soundtracks for the entire decade, and the only live performances he gave were for the Memphis Mafia and various underage female guests behind the gates of Graceland. But two events happened before decade's end that would poise the King for a great comeback: The 1968 NBC-TV special and the 1969 recording sessions at Chip Moman's Memphis studio which resulted in amazingly mature and creative work like "In the Ghetto," "Suspicious Minds" and "Kentucky Rain." Author Gillian Gaar did exhaustive research for the book, including many contemporary interviews with Presley's bandmates and associates. Her most interesting chapters delve into the background behind the TV special - simply titled Elvis, but universally known as "The Comeback Special." Director Steve Binder (who also helmed The T.A.M.I. Show) wanted anything but the cheesy Christmas program that tight-controlling manager Col. Tom Parker insisted upon. Instead, he produced an incredible piece of television loosely tracing the singer's rise with great production numbers, dancing, and live performances. Of course, the show's most memorable sequence showcased Elvis in That Black Leather Suit, informally performing sit-down/stand-up jams with a crack band (including original guitarist Scotty Moore and drummer D.J. Fontana) through a string of hits and favorite covers. Presley's sex was on fire long before the Followill boys sang about it, with the suit almost transforming him into a rock superhero. In probably the book's most, um, offbeat revelation, we learn that Presley was so excited during his performance at a 6 p.m. taping, he actually ejaculated in the leather pants. He also sweated so much that it had to be peeled off his body and dried with hair-dryers to look fresh for the 8 p.m. taping. Both the show and the records found enthusiastic and new audiences. So as the '60s came to a close, Presley was on top of his game again, and he capped it off with the return to full-time performing with a lengthy residency in... Las Vegas - a move commonplace for rock stars now, but unheard of at the time. And while Gaar says the initial shows were full of fiery excitement, any hope for a permanent artistic "comeback" were quickly doused by a domino-effect of factors which eventually lead to his 1977 death at age 42: drugs, overeating, rampant spending, boredom and complacency on stage and in studio, a reversion to substandard new material, schmaltz, despondency, divorce and a manager always looking for the easiest buck and safest route (Parker talked Presley out of starring opposite Barbara Streisand in A Star is Born). But for a brief 2-3 year period, it looked like rock's first superstar could also pull off its first sustainable major comeback (Chuck Berry and Jerry Lee Lewis' efforts during the era notwithstanding). Return of the King makes you wish for a different ending, and despite the occasional dryness is well-written enough that the reader - who knows better - still roots for Elvis Presley to pull it off. Of local note, Gaar recounts Elvis' initial dismal feeling on his six Astrodome concerts at the 1970 Livestock Show and Rodeo. The opening performance on the afternoon of February 27 filled less than half of the Dome, leaving him to muse to a relative "Well, that's it. I guess I just don't have it anymore." Larger crowds came later, one setting a Rodeo record at the time of 43,614, and buoyed his spirits despite the dismal sound system. But as his keyboardist is quoted, "The Astrodome was a purty crummy gig." Jaw Bone Press272 pp., $19.95.