As the music world begins to assess the complicated legacy of the man who crowned himself the King of Pop, there is no denying that Michael Jackson's climb from humble beginnings amid the belching smokestacks of Gary to the top of the charts and worldwide superstardom will rank beside those of Frank Sinatra, Elvis Presley and the Beatles as one of the most extraordinary rags-to-riches stories ever.

Nor is it an exaggeration to say that Jackson, who died Thursday a little more than two months shy of his 51st birthday, made a more profound impact in the arenas of soul, R&B and dance-pop than any other singer or songwriter in history.

Sadly, these accomplishments also will forever be intertwined with one of the most tawdry and tragic public meltdowns that pop culture has ever witnessed. Long shadows were cast by charges of child abuse, behavior that ranged from mildly eccentric to disturbingly bizarre and the star's inability to create worthwhile new music divorced from his personal turmoil throughout the last 18 years of his career.

In many ways, Jackson's biggest musical success turned out to be his biggest handicap, since its beyond-all-measures accomplishments were something he could never top.

Released on Nov. 30, 1982, the singer's sixth solo studio album, "Thriller," is widely considered the best-selling disc of all time, with sales estimated anywhere between 40 million and 100 million copies worldwide. But despite the much-vaunted impact of its genre-blurring sounds on radio and the pop charts -- it spawned six Top 10 singles, including the back-to-back No. 1 hits "Billie Jean" and "Beat It" -- and the fact that its big-budget videos broke the unofficial color barrier at MTV, real fans never thought it his finest work.

That honor belongs to "Off the Wall," the 1979 album that actually pioneered the mix of funk, disco, pop, soul, jazz and rock that he polished for mainstream consumption on "Thriller." With songs such as "Don't Stop 'til You Get Enough" and "Rock with You," and collaborations with superstars such as Stevie Wonder and Paul McCartney, who clearly viewed the then-20-year-old star as a peer, "Off the Wall" is the album hardcore fans reach for, including celebrated acolytes such as Justin Timberlake and Usher.

For that matter, more moving than anything on "Thriller" is the 1972 ballad "Ben," another No. 1 hit and a song that Jackson, right at the start of his solo career, invested with so much emotion that it instantly transcended its origins as a love song to a killer rat from a B-grade horror film.

And, of course, there are the irrepressible, irresistible, unrelentingly upbeat songs of the Jackson 5, the family group that featured Michael and four of his eight siblings. Dismissed as bubblegum pop by some critics during their hit-making prime from 1969 through 1971, in retrospect, they stand as one of the most heartfelt and enduring acts that the legendary Motown Records ever produced. Michael's vocals, in particular, endure, with the prepubescent star somehow singing in a voice wise and soulful beyond its years.

It's one of the great ironies of his career that Jackson's voice pitched higher and more closely evoked a young child the older he got -- though this somehow fit his infamous Peter Pan-like obsession with childhood and refusing to grow old.

While some manifestations of this could be overlooked -- the pet chimp, the amusement park on his Neverland ranch, the bones of the Elephant Man and the rest -- others, like the disfiguring plastic surgery, could not. Nor could the disturbing facts that in 1995, he settled charges of having sexual relations with a 13-year-old boy by reportedly paying the child's family $20 million, and that a decade later, Jackson faced criminal charges for having sex with another minor.

The superstar was acquitted of those charges in 2005, but music industry experts remained divided over whether he could ever rebuild his career. His last two albums, "HIStory" (1995) and "Invincible" (2001), were commercial and critical failures, dominated by songs rife with paranoia and full of weird, messianic images. He hadn't toured the United States in two decades -- his last Chicago shows were at the Rosemont Horizon in April 1988 -- and the first four of the much-hyped comeback gigs set for London's 02 Arena in July already had been postponed, with British bookies laying odds that Jackson would cancel outright.

Now, the question of whether the King of Pop could ever have recovered all or some of his past glories will be just another of the many troubling mysteries always linked to his name.

AN AUTOBIOGRAPHY IN SONG