Ten years after the brutal death of Diana, Princess of Wales, what are we to make of her? Was she, as most of the British public prefer to believe, a saintly creature betrayed and humiliated by the chilly indifference of Prince Charles and his dowdy mistress Camilla? Or was she a far from frail flibbertigibbet whose doe-eyed fragility disguised the mind of a modern Machiavelli? Or was she, perhaps, both?

Tina Brown’s “The Diana Chronicles” (Doubleday, 560 pages, $27.50) sets out to put us right not only on the central point — minx or martyr; victim or vixen — but on a whole collection of subsidiary mysteries, such as whether it was Diana who smuggled herself onto the royal train for a pre-wedding tryst with Charles, or his favorite mistress, Camilla Parker-Bowles. Ms. Brown is in an ideal position to sort out fact from factoid. She, too, is a glamorous blonde who famously upset the decorum of a venerable institution and its devoted followers, though her dynamic editorship of The New Yorker has left a more lasting impression upon the accessibility of Manhattan’s house magazine than the petulant Lady Di had on the accessibility of the House of Windsor.

Ms. Brown casts a sophisticated and skeptical eye over the reams of nonsense which have smothered the Diana myth. Mohammed al Fayed, shopkeeper to the royal family and father of dithering playboy Dodi, who accompanied Diana to her Parisian doom, will be sorely disappointed. He hopes to prove that marriage was in the air and that only the anti-Muslim hatred of the British establishment stood in the way of the star-crossed lovers. Ms. Brown has found no evidence to suggest that Diana had any honorable intentions towards his cocaine-fueled son, whom she was using merely as a dupe to help embarrass her anguish-ridden former husband and his indomitable mother, Queen Elizabeth.

With many of the principals, such as Charles and the rest of the Windsors, remaining silent, and Diana herself leaving a trail of conflicting evidence, Ms. Brown adopts a post-modern approach to dissecting this enigmatic beauty. As a longtime serious student of celebrity and an editor who is steeped in discerning the subtext and the backstory in a narrative as much as the full frontal official version, she is in a perfect position to write the definitive speculative life of a woman every bit as complex and elusive as Marilyn Monroe.

Ms. Brown takes it for granted that we know the bare bones of the story and she offers explanatory glimpses into the strangely frozen world of the British aristocracy, which she makes clear she has little time for, and presents alternative readings of the events. When Diana found herself alone in Buckingham Palace while her young fogey of a husband went about his official and extra-curricular duties, was Diana simply too silly to listen to the advice given her by the phalanxes of royal courtiers, or was she already cunningly plotting to turn the monarchy upside down?

The answer is not simple. Despite calling a succession of witnesses, including the reported words of Diana and Charles themselves, Ms. Brown is hard put to pronounce even on whether the pair were really in love. Despite Diana’s protestations that she had been tricked into a ménage a trois, it seems likely that neither of them were genuinely in love with each other, though both may have been in love with the notion of being in love, which is not quite the same thing.

Ms. Brown is quick to point out, however, how misapprehensions about “the love story of the century” were manufactured. Unable to find Diana’s former lovers, because there were none, Fleet Street erected a virginal façade around her, making her shyness, not her slyness, the source of her sexiness. Diana was from the beginning a mistress of media manipulation, and even when her marriage was failing and she summoned editors to lunch in order to whine to them about her husband’s infidelity, the press continued to write fiction in order to please its readers and boost circulation.

As an example of Ms. Brown’s nimble writing style, try this: “There was no other rival for her heart but twenty-eight-year-old Charles Philip Arthur George, HRH The Prince of Wales, Earl of Chester, Duke of Cornwall, Duke of Rothesay, Earl of Carrick, Baron Renfrew, Lord of the Isles, and Prince and Great Steward of Scotland — or ‘Arthur,’ as he liked to be called when he climaxes.”

Ms. Brown’s sophisticated approach, a triumph of reporting, makes “The Diana Chronicles” a candy feast of royal gossip to be consumed preferably at a single sitting. It will bring the summer to a standstill. Every last quip and quote, snip and sneer, joke and jape about this disastrous marriage is recorded with elegance and interpreted with wise understanding.

nwapshott@nysun.com