Spada, author of film bios of Jane Fonda, Bette Midler, Katharine Hepburn, Marilyn Monroe, Barbra Streisand, and Judy and Liza here girds himself for siblings Shirley MacLaine (see above) and Warren Beatty both at once. Both have matured as artists, won Oscars for their best work, and have reputations as eccentric individualists, Shirley as a mystic, Warren as a mythic stud who believes in ""sequential polygamy."" Now divorced, Shirley maintained a 30-year marriage to Steve Parker, with Parker living in Japan and Shirley in Hollywood or on the road. Unmarried Warren, meanwhile, a nondrinker and nonsmoker who does not care to abuse his body, has carried on his legendary conquests (Joan Collins, Natalie Wood, Julie Christie, Diane Keaton, Candace Bergen, Vanessa Redgrave, Barbara Harris, lager Stevens, Barbra Streisand, Jane Fonda, Britt Ekland, Carly Simon, Joni Mitchell, Goldie Hawn, Mary Tyler Moore, Jessica Savitch, Susan Strasberg, and Daryl Hannah among the more famed--although Warren draws no line and will snap up a hatcheck girl as quickly) until becoming the most notorious womanizer in the history of the silver screen. Says Collins in her autobiography: ""He was insatiable. Three, four, five times a day, every day, was not unusual for him, and he was also able to accept phone calls at the same time."" Says Shirley: ""I haven't seen Warren naked since he was six. I'm really curious to find out if he really has what they say!"" Womanizing also made Warren fabulously famous and extremely picky with script offers long before his first feature (Splendor in the Grass) was released. By then Shirley, three years older, was maturing into her second phase of film fame with her performance as the gold-hearted whore loved by Sinatra in Some Came Running. Warren kept far away from Shirley, never discussed her in interviews--or much of anything else, being a very poor, tongue-tied interviewee. It is warmly rewarding, however, to follow these two troupers through their first successes, their messy, low-key middle periods, and have both achieve phenomenal comebacks, Shirley with The Turning Point and Terms of Endearment and as a best-selling author, and Warren with Shampoo and his first directorial, co-written, starring effort, the serious, romantic epic Reds. No deathless meditation on film acting, this survey of nearly 60 films lensed by the century's most celebrated brother-sister duo is energizing, effortless fun.