One year ago tonight, Katie Couric slipped into the "CBS Evening News" anchor chair, pristine in pearls and white jacket, after a huge media buildup in which she vowed to overhaul the network's stuffy nightly newscast -- and, as a single mother, never go to Iraq because of concerns about her two children.

This week, though, she's broadcasting from Baghdad in 110-degree heat, and the cozy "Hi, everybody" with which she has greeted viewers has been replaced with a more traditional, just-the-facts reporting style while interviewing President Bush -- who had just landed in the war-torn country himself.

It's amazing what bad ratings will do to good intentions.

Couric's trip comes as her nightly broadcast remains stuck in third place -- and amid talk that she'll be gone from the anchor chair in five or six months. It also comes the same week that a book on her is released by Edward Klein, a New York writer, perhaps best known for a critically panned hatchet job on Hillary Clinton -- "The Truth About Hillary" -- and several fawning, improbable books on Jacqueline Onassis and, last but not least, "The Kennedy Curse," which posits, among other things, that Carolyn Bessette Kennedy was a cokehead.

Now he has written an unauthorized biography on Couric -- "Katie: The Real Story" -- containing these bombshells:

She slept her way to the top with a married man.

She terrorized and belittled staffers.

She would deliberately prolong "Today" interviews to cut into Matt Lauer's airtime, and she was nasty to and jealous of Ann Curry.

Her marriage to her late husband, Jay Monahan, was in trouble when he died.

She tried to capitalize on her widowed status to gain viewers.

Is any of this true? We have no way of really knowing, because a quick look at the notes in the back of the book show -- amid all the quotes lifted directly from Star magazine -- that most of the really juicy stuff is, whoops, sorry, from confidential sources.

In Chapter 13, Klein claims Couric suppressed the truth about her husband's colon cancer in order to boost her image during contract negotiations, according to "interviews with a number of friends, family members and colleagues." Then, incredibly, Klein adds that "out of respect for Katie's privacy on this subject, all these sources requested anonymity."

In fairness, a number of people do go on the record for Klein, and it is surprising how many were negatively disposed toward Couric, who reportedly dreamed of anchor stardom from a very young age and didn't care whom she alienated to get there.

But reading about her rise to broadcasting stardom just doesn't pack the same excitement as, say, Eric Sevareid's, which he documented in his lovely 1946 memoir, "Not So Wild a Dream," describing how a Minnesota farm boy became a CBS superstar -- complete with plane crashes in Burma, the London Blitz, brushes with Gertrude Stein and Churchill, and thoughtful, even lyrical insights on what it means to be an American.

Now there was a broadcast journalist's life story.

In contrast, Couric's rise to the top of TV news is interesting, if you like watching plastic flowers grow: from desk assistant to street reporter to backup Pentagon reporter to "Today Show" host, all taking place in the curiously artificial atmosphere of the television news studio: WTVJ, WRC, ABC, CNN, NBC.

And then -- drum roll -- CBS's anchor chair. Becoming the first female network television anchor would have been a thrilling achievement perhaps 15 years ago, but in these days of the Internet and 24/7 cable, it almost seems quaint, like discovering your cranky old uncle really does believe in women's lib.

Which is why all the fuss over Couric's ratings -- and Monday's interview with Bush in Iraq -- seems overblown.

And it's why it's perhaps understandable Klein felt the need to spice up Couric's story with dollops of sex, hubris and screaming matches -- even if we'll never know if a word of what he's written is true.