Criminal Minds: "Our Darkest Hour" -- Agents Jareau (A.J. Cook, left) and Hotchner (Thomas Gibson, right) work with the rest of the BAU team to find a serial killer who preys on his victims in the dark, the fifth season finale cliffhanger of CRIMINAL MINDS, Wednesday, May 26 (9:00-10:00 PM, ET/PT) on the CBS Television Network. Photo: Monty Brinton/CBS ©2010 CBS Broadcasting Inc. All Rights Reserved.