In spite of the introduction lending a certain importance to sources particularly when you often end up with Elsa Maxwell and The Daily Mail, Mr. Frischauer, whose taste runs high on the continental hog (Onassis; Grand Hotels of Europe), has done a collective biography of Khans from Ali to Aly (Ali was the 6th century first). However he really concentrates on the last three -- residenced at the Ritz or St. Moritz' Palace or a villa, commuting between race courses and spas, and proceeding from affair to dalliance. Grandfather, Aga Khan III, did have a serious thought in his head however and laid down the new Ismaili Constitution in the '20's with its religious and domestic guidelines; his son Aly shared his passion for the horses to an even greater degree and sometimes it's hard to separate the nags from the notables; son Karim, of ""serious bent"" to begin with, is just about as unknowable as his jet Mystere implies. And Begum (she's an Aga's Royal Highness) it's hard to keep track of all this -- a Diamond Jubilee with a sari studded with 1200 gems, My Love (he's a horse), Rita Hayworth, Dufys and rupees. . . you're almost aghast.