The FBI's assistant director of national security, Linda Barnes, joins the BAU as they investigate a quadruple homicide of a group of roommates in St. Louis.
Criminal Minds revolves around an elite team of FBI profilers who analyse the country's most twisted criminal minds, anticipating their next move before they strike again.
David Rossi comes out of retirement to help the the Behavioral Analysis Unit lead by Aaron Hotchner, a family man who's able to gain people's trust and unlock their secrets. Also on the team are Emily Prentiss, the daughter of an ambassador and a surprise addition that neither Hotchner or Gideon signed off on; Derek Morgan, an expert in obsessional crimes; Dr. Spencer Reid, a classical misunderstood genius whose social IQ is as low as his intellectual IQ is high; and Jennifer 'JJ' Jareau, a confident young agent who acts as the unit liaison for the team. Also helping the team is Penelope Garcia, the team's audio/visual technician.
Each member brings their own area of expertise to the table as they pinpoint predators motivations and identify their emotional triggers in an attempt to stop them.