When several women in Herndon, Virginia, are found murdered in a similar manner, SSA David Rossi reopens an unsolved cold case that has haunted him for a quarter of a century because he believes the original killer, who is suffering from Alzheimer's Disease, might have returned.

The BAU hits the road to track down a pair of young lovers on an interstate murder spree. Also, Prentiss hears frightening news from her former boss at Interpol.

The BAU travels to Portland to investigate a suspected gang of murderers targeting a new victim each night.

The BAU team searches rural Oklahoma when women are being found murdered after being robbed of one of their five senses. Also, JJ and Prentiss get the cold shoulder from Reid as he deals with their deception about Prentiss' presumed death.

The investigation of a series of bludgeonings in Philadelphia leads the team to the city's boxing scene; Hotch connects with a fellow runner while training for the triathlon.

When married couples fostering young children end up being killed in Seattle, the BAU team looks for an unsub with a maternal-yet-murderous instinct. Also, Garcia fears a possible proposition from Kevin.

When the bodies of two seemingly unrelated victims are found just hours apart in San Diego and Los Angeles respectively, the BAU suspects that that not one, but two killers are working together to commit these murders.

A ritualistic killer is hunted after male bodies are found that have been physically altered. Meanwhile, Reid gets anxious at the prospect of meeting his mystery woman.

The BAU goes to Morgan's old neighborhood in urban Chicago in search of an unsub targeting middle-aged men, and a clue leads Morgan to believe that they are after someone connected to the man who molested him as a child.

The hunt for a methodical killer takes the BAU to Arizona to search for an increasingly devolving unsub, and the team speculates that Hotch is in the running to be the new BAU Section Chief following the death of Erin Strauss.

When skeletons are discovered in the backyard of a home in Virginia, family secrets and past racial divisions are brought to light.

Morgan's visit with a survivor of unusual stabbings in upstate New York leads to more questions about the case.

When prostitutes are murdered in Texas, their deaths seem to have religious overtones; members of the team are put at risk throughout the course of the investigation.

A series of abductions and murders in Seattle send the BAU seeking an UnSub who was abused in the past and is out for revenge. Garcia heads to Texas to confront the man she shot while defending Reid and herself, as he waits on death row.

The BAU investigates random murders in northern Virginia and searches for a conflicted UnSub who has an uncontrollable urge to kill but is also filled with remorse. Rossi receives a visit from a woman who could hold a secret from his past.

When Kate's niece and her best friend Markayla are kidnapped, the BAU suspects an online predator engaged in sex trafficking who poses as a teenage boy.