DOES IT MATTER that artists we admire may have feet of clay? Alfred Hitchcock is now celebrated as one of the glories of international cinema - a Cockney who remained unassailably English, even though he made some of his finest films after moving to America. His image remains that of the dry, unflappable entertainer, rotund and flat-voiced, purveying his tales of violence and sexual betrayal with understated black humour. Everybody's favourite wicked uncle, in fact.

But anybody who has been reading the penetrating series of books on the director by Donald Spoto (of which Spellbound by Beauty, the latest, is one of the most concise) will be well aware that the true, unvarnished Hitchcock was very different from the precisely cultivated public image.

Spoto presents us with a tortured genius: sexually repressed (Spoto, like his subject, has a Roman Catholic background), self-conscious about his weight and celibate, working out cruel sexual scenarios via the exquisite blonde leading ladies of his movies. But is Spoto's the kind of muckraking journalism that writers such as Kitty Kelley trade in with their bestselling character assassinations?

Certainly, the opprobrium hurled at Spoto after his previous books on Hitchcock might suggest that. But the merest glance at Spoto's career demonstrates that he is a very different kettle of fish from the hatchet-job writers. He has written a series of biographies that combine immense enthusiasm for his subjects with a sturdy refusal to ignore their less savoury behaviour; his book on the house of Windsor, Dynasty, rose above the gimcrack royal biography industry to paint a coolly objective portrait of a dysfunctional lineage.

However, for most film aficionados Spoto's books on Hitchcock identify him as a nonpareil film journalist, and those who have attacked these studies of the director have mistakenly assumed that the laying bare of hidden aspects of Hitch's personality somehow represents a diminution of the director's achievement as a film-maker. Certainly, nothing is sacred to the writer.

Hitch's bizarre - often cruel - treatment of his leading ladies dated back to his early classics such as The 39 Steps; desiring that the exquisite Madeleine Carroll express shock in a scene, he consulted the cameraman and then turned to Carroll so that she was the only one on the set who could see that he had unbuttoned his trousers as if to expose himself. The director got his response. By the time Spoto discusses the appearance of Ingrid Bergman in masterpieces such as Notorious, we are in the era when the writer could draw on his own friendships with such actresses.

It was an open secret in the director's circle that he had fallen hopelessly in love with Bergman, and he regaled people with a tale that (even then) must have seemed the product of an astonishing wish fulfilment. He related that after a dinner party at the Hitchcock house, Bergman refused to leave his bedroom until he made love to her. As Bergman says: “Some people really believed his story. I never got angry when it came back to me...I loved him, but not his way.” Tippi Hedren, the director's last protégé, describes even more lacerating behaviour (notably during the making of The Birds) to Spoto.

The director existed within a kind of prison; a physical one. By 1945, he weighed more than 300lb. The morbid obesity rendered any kind of physical intimacy impossible. The genius of his films, of course, is the transmuting of this frustrated sexual energy into the exigencies of classic cinema.

Spellbound by Beauty: Alfred Hitchcock and his Leading Ladies by Donald Spoto
Hutchinson, £20, 229pp Buy the book here from Books First £18.00 including free delivery

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