Ben’s "friends" urge him to attack a nurse, Karen Heywood, after an awkward supermarket interaction.
Early theories suggest a "pack" of killers, but Hotch quickly realizes it is one single, highly disturbed individual leaving the same shoe prints at every crime scene. The unsub is Ben Foster (played by Bug Hall), a paranoid schizophrenic who believes he is being pursued by the ghosts of three friends he killed in a fire when he was a child. These "ghosts" (Matt, Tony, and Yolanda) now haunt him, acting as "imaginary foes" that force him to kill to get them to stop nagging him. [S6E19] With Friends Like These
This episode is a standout for its unique portrayal of the unsub's mental state. By showing the hallucinations as real, active participants in the first half of the episode, the audience feels the same confusion and helplessness that Ben experiences. Ben’s "friends" urge him to attack a nurse,