SEASON 4, EPISODE 401 - When an SUV carrying members of the BAU explodes, the rest of the team fights to save their colleagues and catch the terrorists responsible for the bombing. Michael Steger ("90210") guest stars.
SEASON 4, EPISODE 402 - When a series of murders are linked to a serial killer who was executed a year ago, the BAU must find the connection between him and the current killing spree.
SEASON 4, EPISODE 403 - When Prentiss and Reid go undercover to investigate possible child abuse at an underground cult, they get trapped inside the compound when a federal raid goes bad. Luke Perry ("Beverly Hills, 90210") guest stars as cult leader Benjamin Cyrus.
SEASON 4, EPISODE 404 - A serial killer who disguises his victims' demise by creating car accidents to mask their earlier deaths is the subject of a BAU manhunt. William Mapother ("Lost") and Wil Wheaton ("Numb3rs") guest star.