In the early '50s, when Peter Finch was young, he was considered a potential star for the same constellation as Laurence Olivier and the other great leading men. But a colleague was dubious: "Finch lacks that indefinable something." He was right; Finch never became a big gun, and there was often a strange deficiency in his performances -- too many of which were in dispensable films.

To be fair to Finch, he did improve with age, and he was always sensitive and likable. But there was something withdrawn about him. Great actors have no defenses, but Finch's eyes were translucent, and his voice was somehow stifled, even though it bubbled out of the same cauldron as Richard Burton's.

Although he gave some first-rate performances ("The Nun's Story," "Far From the Madding Crowd"), in the end, they often seemed muted, introverted and forgettable. Despite his rugged good looks, his face wanted to blend with the scenery. It's perfect that his one great role was the repressed gay doctor in "Sunday, Bloody Sunday." An actor in camouflage should know what the closet feels like.

But what a life. As described in these biographies, it sounds like something Lee Tracy would have invented in a '30s newspaper comedy. Kidnaped away from his mother by his cuckolded father in London at the age of 2. Deposited with his crackpot bluestocking grandmother in Paris. Taken by grandma to India for some Theosophist atmosphere. Raised in Sydney, Australia, by sourpuss relatives who beat him. At 16, he fled.

Soon Finch had lost a newspaper job, taken to the open road in the Outback, lived with the aborigines, married a Russian ballerina and appeared in vaudeville. Then a British actor caught him playing Moliere in a glass factory and said, "If you ever come to London, look me up." That was Laurence Olivier.

With that worthy patron, Finch went on to a triumphant West End debut, picked up a reputation as a stage actor and then spent much of his career avoiding the theater. Although there were some good films among the 42 he made -- besides "Sunday, Bloody Sunday," there were "Oscar Wilde" and "The Pumpkin Eater" -- most of them were embarrassments.

There were two more wives -- a lusty swinger and a swaggering Jamaican -- and many love affairs, one with Vivien Leigh. The only constants in his private life seem to have been drinking and confusion. He wept drunken tears over his prostituted art, and although he usually blamed the studios, at least once he admitted, "I've buggered up my own career." But when Peter Finch died of heart failure at the age of 61 in the lobby of the Beverly Hills hotel, no one said the ride hadn't been eventful.

In "Finch, Bloody Finch," Elaine Dundy documents Finch's ride with tireless curiosity. A little too tireless: The book is too long by a third. tAnd she can't always recreate Finch's personal impact -- not only his impact on the screen, but at a meal or in a quarrel. The sense of him as a specific personality can waver, which means the book sometimes reads like the dossier of another nice, tormented, crazy movie star. But in the end it is a success, because Dundy writes with a literary charm and sophistication unheard of in show-business biographies.

Trader Faulkner's "Peter Finch" may be the first print equivalent of those terrible BBC documentaries where people sit in their living rooms talking endlessly, and every so often a voice from this side of the camera goes off. The author knew Finch personally, as a student and friend, and his research surpasses Elaine Dundy's. But the choice of material is indiscriminate, the writing stagnant and the tone oversolemn. In the entire book, there's nothing amusing, except Liv Ullmann's one-page foreword, which is meant to be taken seriously. As with Elaine Dundy, Trader Faulkner's implicit premise is that Peter Finch was some sort of once-in-a-lifetime super-special tragically wasted phenomenon. He may have been just that. But in these two portraits, the words of his old colleague still apply. He lacks that indefinable something.