John Knox

The BAU team searches for a serial rapist in Houston known as "The Piano Man" who has resurfaced and is assaulting his previous victims. Also, Prentiss tries to come to terms with her trauma from last year and with rejoining the team.

As allies and enemies scramble to learn what happened the night of Emily's wedding, the Graysons close ranks to protect their own. But when everyone’s a suspect, it's only a matter of time before they tear each other apart.

Foster’s former patient, one of the founders of a social-networking app, comes to the Lightman Group when she thinks she’s being squeezed out by her partner. When she turns up dead a short time later, Lightman fights against the prevailing evidence to expose the truth behind the murder.

An Iowa teen disappears during her school trip, and the prime suspect is the son of a judge.