A.J. Cook A.J. Cook

A.J. Cook has been dropped from Criminal Minds and will be replaced by a new female cast member during the CBS drama's upcoming sixth season, a source close to the show tells TVGuide.com.

The source cited "creative reasons" for Cook's departure, not financial considerations by the network as initially cited.
Cast member Paget Brewster is in negotiations to return for a reduced number of episodes. Thomas Gibson, Joe Mantegna, Shemar Moore, Matthew Gray Gubler and Kirsten Vangsness are all expected to return.

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With the exception of the pilot, Cook, 31, has been a regular on the crime procedural since Season 1. She missed six episodes during the fourth season when she went on maternity leave. Her pregnancy was written into the show, giving her character, media liaison Agent Jennifer "J.J." Jareau, a son.

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Brewster, who plays Agent Emily Prentiss, joined

Minds during Season 2, replacing Lola Glaudini.Calls to Cook's rep were not immediately returned.Will you miss J.J.?