For Katie Couric, Diane Sawyer and Christiane Amanpour, the moment of truth is about to arrive—or at least a book-length facsimile thereof.

News executives and network publicists have been distracting themselves from this summer’s seriously depressing or otherwise alarming world events by passing around and poring over bound galleys of The News Sorority, veteran journalist Sheila Weller’s gossipy chronicle of the rise (and occasional stumbles) of three of television news’ best-known women.

In Weller’s narrative—which, as the subtitle indicates, aspires to document “the (Ongoing, Imperfect, Complicated) Triumph of Women in TV News”—Couric comes off as brash, striving, self-absorbed, and occasionally insensitive to the realities faced by her less well-compensated coworkers, yet steeled by personal tragedy (the cancer-related deaths of her husband and her sister) and capable of big-hearted generosity.

Sawyer is a Machiavellian, often-inscrutable workaholic who uses her seductive charm and good looks to professional advantage and torments news producers with her relentless perfectionism and insecurity—an apparent consequence of a fraught relationship with her judgmental, formidable mother (who once sent the adult Sawyer into a self-flagellating death spiral, Weller writes, when she criticized how her TV star daughter had made her bed).

Amanpour is the reigning queen of the warzone, more physically courageous and resourceful than her male colleagues in perilous combat situations, but with an occasionally off-putting sense of moral superiority which, along with her posh British accent, sometimes renders her brittle and inaccessible to American audiences—a factor which seems to have hampered her career.

All three, in Weller’s account, are superb journalists who have risen to the top of their profession through sheer talent, brains, and hard work in an industry whose culture, even in the second decade of the 21st century, remains more than vestigially sexist. In one representative anecdote, CBS News Executive Vice President Paul Friedman publicly muses on an open audio line about which female anchor looks worse without makeup—Sawyer or Couric.

“I was blown back in my chair,” a female producer tells Weller. “What did it say about a man in senior management that he didn’t know he shouldn’t say that, of his boss [Katie], out loud?”

The expansive book, which runs to 471 pages sans index (the section that will undoubtedly be the most closely read by folks in the biz), won’t be officially on sale until its Sept. 30 release date. But Weller and her publisher, Penguin Press, have been working overtime to generate buzz—along with a fair amount of teeth-gnashing—by posting items on Facebook and distributing early copies to favored media outlets, including The Daily Beast.

Some highlights:

*When Sawyer was up for a job at CBS News’ Washington bureau after years in the press office at the Nixon White House and then helping the disgraced former president with his memoirs in San Clemente, Dan Rather advised CBS News President Bill Small: “Don’t hire her!” Rather later admitted he’d been wrong.

*Sawyer’s longtime live-in boyfriend, investment banker (and former and future diplomat) Richard Holbrooke (who later married journalist Kati Marton), “did the dirty work for her,” a CBS staffer says, “and he drove everybody crazy… He would call the executive producer [of the CBS Morning News] every day to say, ‘Why doesn’t Diane have more to do?’…”

*When 60 Minutes impresario Don Hewitt hired Sawyer for a plum perch on his top-rated Sunday show, a prominent CBS producer explained her rapid rise this way: “You gotta understand—the guys who own and run the networks all have the shiksa disease.”

*When Sam Donaldson, Diane’s internally popular co-anchor on ABC’s Primetime magazine show, returned from prostate cancer surgery and did a physically grueling story about a survivalist living in the wilderness, one of Weller’s ABC News sources says, “Diane called everybody and said, ‘That was a really terrible piece—let’s make sure it doesn’t happen again.’”

*Sawyer’s famous rivalry with Barbara Walters for ratings-grabbing interview subjects was akin to mortal combat. “Barbara and Diane were determined to kill each other—to wipe each other off the face of the earth,” says an ABC News staffer.

*After toiling at NBC Nightly News and leaving to write a novel when he didn’t get the executive producer’s job, Ben Sherwood angled to run Good Morning America, where Sawyer was the lead anchor in the early 2000s. “Ben, who was as cunning and seductive as Diane, really wooed Diane,” says an insider. “He wrote her emails…‘Why did you do this?’ ‘Here is where I think you’re going wrong.’ That’s how he wormed his way in.”

*After only six months of running GMA, Sherwood left the job, officially to care for an ailing parent, but actually because Sawyer had lost faith in him. “Ben is just so weak,” she said privately.

*Sherwood ultimately returned as president of ABC News, having charmed network chief Anne Sweeney and Disney Chairman Bob Iger. “But now he wasn’t beholden to Diane,” says a Sherwood pal. “With Ben, I don’t think he gives a rat’s ass” what Sawyer wants. “Ben’s gonna stick it to her. She will pay dearly. She might have met her match in Ben.”

*Couric and Sawyer competed relentlessly for “gets” both when they hosted rival morning shows—Couric at NBC’s Today—but with radically different approaches.

Weller writes: “When a friend of Diane’s, a public figure, was being pursued by Katie’s people, the wooed eminence got a call from [Diane’s husband, the famed director] Mike Nichols, who said—in a very nice way, to be sure—that he and Diane would essentially cut off all social contact if their friend appeared on Today.”

When Diane beat Katie on an interview with a 57-year-old woman who’d given birth to twins, Katie mused aloud, according to a person who heard the comment: “I wonder who she blew this time to get it.”

*After the attacks of 9/11, Amanpour defied then-CNN president Walter Isaacson’s attempt “to get all the reporters in the Middle East to skew their stories more favorably to Israel.” Instead she aired a critical report about the Israeli destruction of an Arab village, without including the Israeli government’s point of view. “Christiane had the power to push a piece through,” says a CNN insider.

*When Couric became the first woman to front a network evening news program alone at CBS, she wooed iconic anchor Walter Cronkite over a couple of dinners, and the old man’s blessing was such that he recorded the introduction to the broadcast. Later Cronkite privately expressed discomfort with Couric’s allegedly soft-news style.

*Sawyer maneuvered her former GMA co-anchor, Charlie Gibson, out of the anchor chair at World News. “In the summer of 2009 Charlie had lost his momentum and Diane moved in for the kill…Charlie told people that he was called into David’s [Westin’s] office and told, ‘You’re out.’”

*In early 2010, as CBS News was facing massive layoffs, and prominent talents like Lesley Stahl were being asked to take pay cuts, Couric, who was famously making $15 million a year, gave a breezy interview to Harper’s Bazaar boasting about her great legs, illustrated with a glamorous movie star photo. Weller writes: “Irrational though it might have been, it felt like Katie was rubbing in her privilege while so many women saw themselves, or their friends, cleaning their desks and saying goodbye.”

*Amanpour was angry when, despite putting her life on the line repeatedly to cover wars for CNN, network execs declined to give her a show on CNN’s all-important U.S. outlet, instead giving a program to Fareed Zakaria, an academic and magazine editor who had never faced danger under fire. Instead she got a show on CNN International.

Execs told her she needed to brush up on her analytical skills—something Zakaria had in abundance. “She didn’t buy this explanation that he was great at what he does and that he does something entirely different,” a CNN insider explains. “She was very offended that we hired him to do what she saw as her dream job.”

So far I’ve heard some private grumbling but also admiration for Weller’s reporting from newsbiz insiders who’ve perused the galley. Weller—who spoke extensively to friends and associates of the trio, with the principals’ permission, but not directly to Couric, Sawyer or Amanpour—says the response so far as been a decorous but intriguing silence.

Representatives of Couric and Amanpour declined to give me on-the-record reactions to Weller’s account. Sources at ABC News, speaking on behalf of Sawyer, sought to dismiss the book’s portrayal as overwrought and occasionally wrongheaded—especially Weller’s detailed reporting about the increasingly tense relationship between Sawyer and ABC Television Group President Ben Sherwood, who started out years ago as her intern and acolyte, according to Weller, but ended up as her less than enthralled, occasionally impatient boss.

“These claims are just too ridiculous to even consider,” said a self-identified “friend of Diane’s,” pointing out that last week the 68-year-old Sawyer, who as of Sept. 2 is vacating the ABC World News anchor chair in favor of David Muir, cohosted a farewell party for Sherwood, who is relocating from New York to Los Angeles to assume his new, network-wide duties.

Former ABC News President David Westin, whom Weller portrays as Sawyer’s corporate handmaiden until he allegedly fell out of her good graces by not naming her top anchor after the ailing Peter Jennings left the job and was replaced by Bob Woodruff, told me on Monday that he didn’t even remember that the book existed until a former aide reminded him that he’d heard about it five years ago, when Weller was beginning her research.

“Certainly she did no fact checking with us,” Westin said, referring to himself and his wife, Sherrie Westin, an ABC News executive who, like David, was married to someone else when they met at the office. “It seems to me like ancient history, whether fact or fiction.”