The singing, dancing, acting, power-coupling superhuman known as Beyoncé has held no-last-name-necessary status for almost a decade now. Yet somehow against all the rules of our gotcha tabloid society she steadfastly retains an old-fashioned, almost Garboesque mystery in her private life, granting only the occasional, pleasantly evasive interview. We are left to glean what we can from her songs and performances, which, though strikingly dynamic (only the dead of soul and lead of foot could resist smashes like ''Crazy in Love'' and ''Irreplaceable''), remain oddly disconnected from Ms. Knowles herself, who appears otherwise as serene and unblinking as a beauty queen.
On her third solo CD, which purports to be her most confessional yet, does she finally break through her superstar scrim? Not really. But I Am...Sasha Fierce does offer two compelling sides of the singer. The album is a two-disc set, one the work of ''Beyoncé'' (romantic, vulnerable,soft), the other by her alter ego, ''Sasha Fierce'' (aggressive, sexual, and, well, fierce).
The first two singles one from each disc, released simultaneously demonstrate the contrast between her dueling personae. The ''Beyoncé'' disc's heartrending ''If I Were a Boy'' soars with melodic swells and unwavering in-his-skin sentiments (''I think I could understand/How it feels to love a girl/I swear I'd be a better man''). On the other hand, ''Single Ladies (Put a Ring on It),'' from the ''Sasha'' half, is all bouncy hand claps and post-breakup sass (''Kept crying my tears/For three good years/You can't be mad at me''), a giddy, high-stepping hybrid of lyrical kiss-off and fizzy jump-rope jam.
On ''Beyoncé,'' there are some lovely ballads, including ''Disappear,'' with its sweet guitar-picking and delicate harmonies, and the soaring ''Halo'' and ''Ave Maria'' (the latter does riff on the classic aria, but it's not an actual cover). And several of the high-gloss bangers on ''Sasha'' are more than equal to the gauntlet laid down by ''Single Ladies.'' ''Diva,'' with its metallic kick drum and sly vocal stutters, carries itself like the feminine companion to Lil Wayne's hypnotic summer hit ''A Milli,'' while the crunk-dusted come-on ''Video Phone'' and the spiky, Europop throb of ''Radio'' expertly taunt the boys and fill the dance floor.
The collection might have been better served had she edited it down to one disc, rather than belabor what ultimately seems like a marketing gimmick. And while fans will surely speculate, there's little in the lyrics that feels more revealing than previous emotional fire-starters such as 2006's ''Ring the Alarm.'' But who said we had a right to that, anyway? For all the pop-fantastic satisfaction that Beyoncéthe entertainer provides, the public can surely reward her by leaving Beyoncé the private citizen well enough alone. B+
DOWNLOAD THIS: Listen to songs from the new album on Beyoncé's myspace