According to this devastating and often heavy-handed critique, Ayn Rand, whose novels The Fountainhead and Atlas Shrugged exposed millions to her philosophy of virtuous self-centeredness and capitalist freedom, was an oppressive personality whose Objectivist movement demonstrated all the classic elements of a destructive cult (its messianic leader and its separation of group members from family and friends). Walker presents his subject as an arrogant, dogmatic bully who brooked no criticism and as a repressed narcissist who feared her own emotions and hid behind a glorification of reason. He concludes that Rand was no more than a third-rate pop-novelist of propaganda fiction and that her ""vulgar Nietzschean"" philosophy's obsessive concern with the overachiever--who requires protection via absolutized individual rights--contributed to the movement's cultish aspects. Walker also savages self-esteem guru Nathaniel Branden, who was Rand's protege and extramarital lover; their explosive breakup in 1968 pulverized the Objectivist movement, whose contemporary schisms and crosscurrents he ploddingly tracks. In a vitriolic chapter on Federal Reserve chairman Alan Greenspan--a one-time member of Rand's inner circle--Walker unpersuasively contends that this banker's ""inflation-obsessed"" policies grew out of Rand's theories. Those who find Rand's self-styled philosophy outre may not find much of interest in this scathing, albeit clumsy, expose. Others will find it a useful corrective to the Rand mystique. (Feb.) FYI: Branden's tell-all account of his affair with Rand and his role in the Objectivist movement is being reissued in a new edition in March as My Years with Ayn Rand: The Truth Behind the Myth (Jossey-Bass, $19 480p ISBN 0-7879-4513-7). While he does criticize Rand personally, his treatment differs from Walker's in that he still reveres her as a philosopher.