When an undercover cop in Baltimore involved in a mob investigation goes missing, the BAU believes a serial killer rather than organized crime has something to do with his disappearance. The probe leads to several unsolved missing persons cases.

Elle, along with many others, is held hostage on a train in Texas by a paranoid schizophrenic who is convinced that the U.S. government is monitoring him. Hotchner and Gideon are forced to play into the man's fantasy to save the people he has taken hostage.

A serial killer reappears after 20 years of silence and contacts the BAU with the promise he will kill another victim in the next five days.

The BAU works to capture a serial killer who has evaded capture by altering his appearance.

The BAU has reason to believe a series of murders might have been committed by two people working as a team after the victims' families receive DVDs after each crime that includes psychological attacks.

The daughter of high-powered diplomats, Special Agent Emily Prentiss joins the team, and she must convince Gideon and Hotchner she deserves the job based on merit and not on her family connections. The BAU is then called to St. Louis to investigate two serial killers who appear to be competing with each other. By setting a trap based on one killer's profile, the team creates a media event by which to capture the second killer.

The BAU is called to investigate after the bodies of missing people are discovered in a remote region of the Idaho wilderness. The gruesome find also leads the team to determine the unsubs have been hunting humans for sport.

The BAU travels to Portland to assist local authorities in investigating the disappearances of people who are new to the city and have no strong social ties.

The new sheriff in Fredericksburg, Virginia, requests the BAU's assistance in the investigation of a series of mutilation murders that appear to mimic similar crimes that had occurred over two decades earlier.

The team members try to identify a stalker before he can attack a woman who is being stalked in Silver Spring, Maryland. Meanwhile, Hotch and Rossi are called as consultants on a possible battered woman syndrome murder case in Boston.

The BAU joins the manhunt to catch a serial killer who conceals the manner of his crimes by staging car accidents.

The BAU team suspects a member of an affluent community in Atlanta is responsible for the disappearance of a local young woman and that the suspect may have worked with an accomplice

When profiling a series of child abductions and murders, the team discovers that one of the cases may not be the handiwork of the serial killer they apprehended.

The BAU must determine what caused a disturbed man to murder several people at a pharmacy before he harms anyone else.

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

The BAU is called upon to profile the past of an ex-convict and help stop him after he escapes from custody and embarks on a violent killing spree.

The BAU is called by local authorities in Ashburn, Virginia, to profile a predator who may have been abducting children for at least eight years.

A series of rolling blackouts in the city of Los Angeles lures a serial killer out of hiding, giving him renewed opportunities to continue his killing spree.

While JJ attempts to reunite a family whose daughter has mysteriously disappeared, her BAU family braces for the loss of one of their own.

Morgan suggests that a man has been rehabilitated and aids in his parole, but later regrets his decision when the man murders someone days after being released.

After a series of murders, Prentiss becomes suspicious of a former nemesis, and fears for the safety of her team.

As the BAU searches for a suspected human trafficking ring when the bodies of two missing persons are found in the trunk of a car, Unit Chief Aaron Hotchner intimates there could be changes within the team due to budget cuts as Jennifer "JJ" Jareau returns to the FBI. The team is also assisted by SSA Andi Swan, the head of the Domestic Trafficking Task Force.

The BAU team is at a crossroads as they are questioned by a Senate Committee for their retaliatory actions in the wake of Prentiss' loss, but an unexpected familiar face could help them win their case and keep the team together.

The BAU team looks into the real reasons behind an apparent mass suicide of a small group of youths at a military academy. Also, Hotch and Morgan butt heads when a team member could be in jeopardy.

As the BAU team continues to pursue the bank-robbing serial killers, the team determines that the suspects have a bigger target in the Nation's capital, and with one of the team still a hostage, they must work quickly to diffuse an explosive situation. Also, wedding bells ring for one of the BAU, and Prentiss ponders her future.

When a Texas prisoner escapes during a transfer, he leaves behind victims with his unique trademark, sewing their mouths shut, a signature the BAU remembers as unique to the UnSub "The Silencer." While they investigate who he was and who he's become, the BAU also gets to know the newest member of the team.

A writer's daughters vanish on the anniversary of their mother's disappearance, which leads the BAU to investigate the man as a possible suspect.

The Replicator zeroes in on the BAU when the killer targets one of the team as the next victim. Also, the BAU is called in to investigate a string of deaths in Manhattan tied to apparent ecstasy overdoses, and Hotch discovers that his estranged brother, Sean, is caught in the middle.

The BAU meets their new section chief, Mateo Cruz, who, unbeknownst to them, shares a long work history with JJ. Cruz joins the team as they comb the streets of Baltimore for an unsub who leaves victims unable to communicate.

Though Rossi is sad because his favorite bar is closing, the team goes to Boston to solve a series of strangulations.

The investigation in Texas reveals a deep web of corruption; Garcia must save a friend.

The BAU team investigates a series of murders in Bakersfield, Ca, which have left the victims unidentifiable. New agent Kate Callahan joins the BAU fold, and assists in the effort to solve the cases.

The BAU revisits its origins when they look at one of Rossi and Gideon’s old cases to track a killer that got away.

When a family of four is abducted while on vacation in Barbados, the BAU is called to assist Unit Chief Jack Garrett and his International Unit on their investigation. Garrett and his unit, the FBI's top division for handling cases involving Americans abroad, work jointly with Hotch and his team when they discover that this case matches one the BAU investigated last year in Florida.

When an UnSub targets the BAU, and the team goes into action to find out who is responsible.

The BAU is shocked when Hotch is apprehended by a SWAT team and suspected of conspiracy, and as the team scrambles to prove his innocence, they suspect a larger plot is on the horizon.

When three children disappear while riding their bikes on the same path as a similar unsolved disappearance 30 years ago, the BAU team comes in to investigate.

When a BAU member gets in trouble in Mexico, the team enlists the services of the International Response Team for their help.

The BAU investigates an urban vampire who kidnaps his victims at night and holds them underground in the sewer system; Reid makes a difficult decision in prison.

The BAU team’s investigation into the home invasion and attempted homicide of a police chief’s wife uncovers a world of secrets in a small town in Virginia.

The BAU is called to Oklahoma to investigate a murderous clown terrorizing the sleepy town of Guymon.

When Reid and Garcia are abducted by Benjamin Merva, it's up to the rest of the team to find them. The BAU finds surprising clues in their own history to solve why the two heroes have been targeted by a mass murderer. It's a race to save them before a Believer's prophecy is fulfilled.

Following an explosive face-to-face encounter with Everett Lynch, a.k.a. “The Chameleon,” Dr. Reid suffers from a brain injury and, while experiencing hallucinations, is visited by ghosts from his past. Also, the BAU makes a shocking discovery about Lynch that affects Rossi personally, and the entire BAU team comes together to celebrate Rossi’s retirement.

When a family annihilator abducts a teen girl, the Behavioral Analysis Unit works the case on either side of the country to save her. But an unlikely connection to a mysterious kit leads to a bigger investigation and at the center of it is Penelope Garcia.