Criminal Minds airs an all-new episode this Wednesday, "Into the Woods." Rachel Nichols makes her debut on Criminal Minds the episode following that, airing December 8.
As FBI cadet Ashley Seaver, she assists Reid, Prentiss, Hotchner, Rossi and Morgan as the BAU searches inside a gated New Mexico community for a killer targeting women.
It's been hotly debated whether the casting of Nichols is meant to replace A.J. Cook, how long her character will stick around or what exactly her role will be. Stay tuned.