The BAU team searches for a serial killer who is preying on married couples. Also, Hotchner looks to one of the team to fill JJ's vacant role.
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Criminal Minds Season 6 Episode 3 Quotes

Morgan: You know, parents are supposed to protect their children.
Prentiss: Well, sometimes they don't get the memo.

Morgan: Rossi, what's in the box?
Rossi: Evil.