When the Girl with the Golden Curls wed The Lad with the Lightning Smile, despite the fact that both were recently divorced from former mates, the world went wild. On the Fairbanks' honeymoon in England, the first Beatles-type pandemonium burst over London and the adored duo was nearly crushed to death more than once. This was not so distant from the impact on Mary of Fairbanks' hyperkinetic vitality (he never drank), personality, and childlike enthusiasm. Mary however had something of the Jekyll-Hyde about her: she registered as ""America's Sweetheart"" only on the left side of her face--the right was ""squinched-up"" and rarely photographed. Uncontainable Doug could not slow down: he bought The Virginian as a showcase for himself, then found he couldn't play the easy-goin', lazy-drawlin' Vuhginian--and sold the rights. To compare Herndon's Doug-Mary (utter Happy Cloud Land at Pickfair; the founding of United Artists with Chaplin and Griffiths) with Gary Carey's Doug & Mary (above) is to make Viennese distinctions between Ã‰clair fillings. Herndon has more facts and is more forthright about Mary's alcoholism and wildly alcoholic family--but Carey has more material about brother Jack's horrors with the bottle and about Doug's later years with Lady Sylvia Ashley (Mrs. Clark Gable later) and Mary's with Buddy Rogers. The real measure is cholesterol and by that scale Herndon out-gaga's Carey.