Continuing the phenomenal story in The Betsy, The Stallion reintroduces the Hardeman family and the cutthroat world of their vast automobile empire, where the stakes are high and every man, and woman, is a gambler.     Loren Hardeman, known as “Number One,†is gradually transferring control of Bethlehem Motors to his grandson, Loren Hardeman III—a man possessed with his father’s cunning, but sadly lacking in his ability to go for the kill. So when Angelo Perino, an outsider previously nurtured by Number One, threatens the position held by Hardeman III, what ensues is a battle of wills in which integrity takes a backseat to animal instinct, and in which there can only be one winner.     Bursting with huge ingredients of lust, greed, sex, and intrigue—and a plot full of twists and double-crosses—this is Harold Robbins at his sizzling best.