A.J Cook and Esai Morales

Criminal Minds' ninth season, premiering Sept. 25, "is shaping up to be the season of J.J.," reports A.J. Cook of her character, who was written out of the CBS procedural during Season 6. (Fan backlash led to Cook's rehiring for Season 7.) "We're going to use the serendipitous gift of Season 6 to explain with flashbacks what happened when she was working for the Pentagon and why she came back as a much tougher character. I've never had a chance to flex my acting muscles like this on the show!"

J.J.'s missing year involves new recurring character FBI agent Mateo Cruz (Esai Morales), who debuts this fall. "They share a pretty dark secret that comes back to haunt them," says Cook, hinting that J.J.'s happy marriage to Will (Josh Stewart) could be threatened. "People are going to be confused and angry, but it's all going to make beautiful sense to our audience when we explain it in our 200th episode." That show, tentatively scheduled to air Feb. 5, will also feature appearances by characters long absent from the series. 

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