Now that Emily Prentiss has left the Behavioral Analysis Unit — again — Agent Alex Blake (Jeanne Tripplehorn, with Thomas Gibson) will take her place on Criminal Minds' September 26 season premiere. Blake, a linguistics expert, made a name for herself by helping solve the Unabomber case—and also by clashing with superiors over the investigation of the post-9/11 anthrax attacks.

"The Unabomber case gave her a halo within the FBI, while the Amerithrax case fitted her with a noose," says executive producer Erica Messer. "She took the fall for a linguistics flub."

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