With Gideon still missing, Hotchner puts in for a transfer and Prentiss tenders her resignation, but both are drawn back to work by a serial killer targeting women in a particularly heartless fashion.

The unit works against the clock when a little girl disappears in a mall, believing a serial killer has struck a second time and the first girl died within an hour of abduction.

A high priced call girl that is killing her clients must be found and stopped.

A man is threatening to kill a doctor's son and is killing a man a day until he is successful. Meanwhile, Hotch's absence is noticed by Prentiss.

A hitman targeting people in some way guilty of children-related crimes brings the BAU to Rossi's home town.

The BAU team races to help Hotchner find The Reaper and save his family before it's too late.

While Agent Hotchner takes a leave of absence from the BAU, the team must regroup to solve a home invasion case.

The BAU go to Detroit to catch a man who burns his victims alive during the pre-Halloween celebration Devil's Night.

The BAU are called to Louisiana to get information from an autistic boy who has witnessed his parents' abduction. Meanwhile, Prentiss calls in two old colleagues to track down Ian Doyle.

The BAU is called to a North Carolina mountain town after a woman is found badly injured and another is missing, and they discover that these two are not the only victims.

The team travel to Boise,Idaho where a serial killer is murdering the survivors of a high school massacre that took place exactly ten years earlier.

The BAU heads to Atlanta, where stabbings of prostitutes lead the team to suspect more than one unsub.

In this first part of a two-part season finale, the BAU encounters a gang of bank-robbing serial killers in the nation's capital. As the team tries to negotiate the situation unfolding inside a bank, one of the team is taken hostage.

In part two of the season finale, the BAU races to understand the ultimate goal and core dynamic of the remaining Face Cards and their design in keeping Will captive and alive.

The team races to find a connection between two families, one murdered and the other abducted.

The team travels to Miami to track a killer who murders hookers in a style similar to animal slayings.

As The Replicator hones in on one of the BAU, Hotch gets a call from his estranged brother when party people in New York begin "boiling" from the inside out.

The BAU race a father who kidnapped his daughter to the border while Hotch has visions while fighting for his life in surgery.

The BAU must track down a killer who sends their victims a warning before poisoning them with arsenic, without ever seeming to come in contact with them.

On October 30, 2014, a frightened eleven year old Joshua Parker is found at a Halloween fair in San Diego. He went missing on Halloween day the previous year. His case mimics that of Tommy Wilcox, who went missing on Halloween 2012 in Los Angeles, only to be found on Venice Beach October 30, 2013, alive but he who eventually died of malnutrition a few hours later. Joshua, however, is expected to live. Both boys had atrophied muscles, and had splinters and puncture wounds, although Joshua seems to have been fed somewhat properly. Both boys were also considered troubled, Joshua who was never listed officially as missing since he was a chronic runaway. The problem for the BAU is that Tommy's captor, Rodney Tanner, who confessed to the crime, is currently incarcerated, meaning that he either had a partner, there is a copycat loose, or that his confession is a lie. They have to figure out this issue before another troubled early or pre-teen Caucasian boy is abducted in the next day. Reid comes to the conclusion that the boys were housed in a homemade wooden box, which accounts for all their physical issues. Discovering a case similar from the past of boys so confined, especially as it relates to Halloween, may provide clues as to the identity of the unsub.

When a family from Maryland is found murdered at their dining room table, the team tracks down other family members and friends to uncover secrets and details from the past in hopes to find out what may have led to it, and to catch who is responsible. Also, Hotch must try to make peace with his father-in-law, Roy, (Ed Asner) after discovering he's been diagnosed with Alzheimer's, and it has become painfully noticeable.

The team works to clear Hotch's name after he's arrested by the DOJ for conspiracy.