Marilyn Monroe: For most Americans in the second half of the 20th century, the name alone was a sentence. She was Venus, beamed into still photographs and onto movie screens directly from the Milky Way, vulnerable and childlike and, when she wanted to be, achingly funny, with goodness knows what darker qualities in reserve. Other models and movie stars more closely approached physical perfection, with more symmetrical facial features (Gene Tierney), longer legs (Juliet Prowse), more stylish physiques (Audrey Hepburn), more exquisite rear ends (Brigitte Bardot). Physically, though, Monroe — five feet six, a size five when she was in her best shape, singing Happy Birthday to JFK on national TV — enjoyed a couple of unique perfections.

Her breasts? Well, yes, they were beautiful, and, although nowhere near as large as, say, Marie Wilson’s, they did something unusual: The muscles beneath them gave them an upward tilt that seemed almost anti-gravitational. Yet, in terms of Monroe’s physical endowments, the pair I was thinking of were her mouth — which in photographs evokes a countless variety of emotive responses — and her intrinsic glow, a property of her skin, on which many of those who photographed and filmed her remarked with wonder. What made Monroe a goddess wasn’t her body per se: It was the alchemical process between her body and what animated her from within. After she died, 50 years ago at the age of 36, under circumstances that are still inconclusive, the alchemy was reduced to mere chemistry: a toxic overdose of barbiturates and chloral hydrate, deemed a probable suicide at the time by official sources but, in the decades since, considered an accident —or even murder —by prominent biographers.

According to biographer and British pop culture chronicler Keith Badman — his Marilyn Monroe: The Final Years was first published in England in 2010 — almost 700 books about (and by) Monroe have appeared so far, a formidable pack for any new biographer to confront. Badman peppers his prose with sentences that begin “I can reveal” but fails to support them with a bibliography or a single footnote. He offers a sort of countdown clock to Monroe’s demise, minute by minute the closer it gets to the end (Badman actually compares himself to Sherlock Holmes), and thus his biography seems merely sensational for its first half. Indeed, the other biographer here, Lois Banner, a distinguished professor of history and gender studies, dismisses Badman’s book out of hand for its lack of scholarly apparatus in a footnote of her own new book, Marilyn: The Passion and the Paradox.

Badman could have obtained some of his information — specific times, specific sums for expenditures, specific knowledge of the hour-by-hour whereabouts of John and Robert Kennedy, rumored to be Monroe’s lovers and, for some speculators, involved in ordering her death, possibly by a drug-laden enema — only from documents whose sources he manages to hide. These might include police reports, transcripts of phone conversations (Monroe’s phone was apparently double-bugged by the FBI and the mobster Sam Giancana) and presidential papers, but the reader can only guess. To understand why he’s written his book, you have to read to the last page: “I seriously hope that, some day, the charge of ‘probable suicide’ on Monroe’s death certificate will be changed to simply, ‘accident.’ She deserves this. She has not earned the stigma which suicide brings. . . .”