Remember when Katie Couric was on The Today Show and she was kind of marketed as the girl next door? She was cute, perky and sweet — or at least that is what they wanted us to believe.

Apparently, the reality of the co-anchor's personal style is quite a bit different than what we have seen over the years, and a new book is about to blow the lid off Couric's mean-girl antics.

Sheila Weller has written The News Sorority in which she spoke with several industry insiders who are familiar with the iconic reporter's treatment of coworkers. While things between Today Show anchors always seemed civil on air, sources say that behind the scenes Couric was really nasty to Ann Curry.

"Katie was a bully and Ann was the victim. Katie often threw Ann off balance by criticizing Ann's clothing choices just before they went on air. She would look at someone and say, 'I really think you're clever, but why is your script so horrible?' She was mean. And no one was safe from her zinging."

Couric eventually left the morning show in favor of anchoring CBS Evening News. A few years after that gig, there were rumors Couric might be heading back to NBC, but apparently she had really left a permanent mark at the network.

According to Weller's sources, no one wanted Couric to return, and they were relieved when she took a different job.

Weller has a pretty good résumé: She has written for Vanity Fair and The New York Times. Her scandalous tell-all is set to hit bookstores Sept. 30.

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