After a fourth woman goes missing in Seattle in a period of four months, the BAU is brought in to track down the serial killer before he kills again.

The BAU investigates a serial rapist who had been attacking young women at religious schools and stopped for six weeks. He has resumed his attacks, but is now targeting a different demographic of women. Elle makes a decision that could end her career with the BAU.

The BAU travels to Ozona, a small Texas community, to investigate the murders of children. Meanwhile, Elle is having readjustment issues after being shot, and Hotchner becomes worried about her when she misses a mandatory psych evaluation and isn't answering her cell phone.

The BAU travels to Seattle to identify and catch a serial bomber who has been terrorizing the city and targeting centers of automated techology. Working with the author of a science fiction novel that has become a guide for the bomber, the team attempts to determine why certain sites have been chosen as targets.

The BAU is called to investigate a series of murders of prostitutes in the nation's capital and Reid suspects a teenager he met asking for his help is guilty of the crimes. The case becomes complicated when a congresswoman, who about to make a speech to praise the city's lower crime rate, threatens to take away the case if SSA Hotchner calls a press conference to discuss it.

Gideon is pitted against the scariest and most evil murderer in his entire career. When the BAU confronts the sadistic killer in a remote diner in the Nevada desert, the local authorities want to move quickly and make an arrest. But Gideon bides his time as he attempts to persuade the man, who has sworn not be captured, to reveal the whereabouts of a woman he is holding hostage.

In this special two-part episode, the BAU is called to investigate after a wealthy couple is murdered in their home following a Super Bowl party. The team pursues what they believe might be multiple killers who use webcams to record murders and upload the tapes on the internet. Hotchner, Morgan and Prentiss soon discover the unsub is actually one man with multiple personalities. As they close in on the killer, Reid faces a life-threatening situation.

In this conclusion of a special two-part episode, finding the serial killer becomes critical to the BAU when the team realizes Reid is being held captive and a live feed of him being tortured is shown on the internet. Meanwhile, Reid's troubled childhood is revealed in flashback sequences as he drifts in and out of consciousness.

Elizabeth Prentiss, a foreign ambassador and SSA Emily Prentiss' mother, seeks the aid of the BAU when a Russian immigrant is kidnapped and held for ransom.

When the prolific serial killer Frank returns and murders Gideon's girlfriend in his own apartment, he starts his own investigation. The BAU is forced to circumvent the local authorities to help Gideon find Frank.

In the first of a two-part story, the BAU pursues a cannibalistic serial killer in Bridgewater, Florida, that leads Morgan to a crisis in his faith. Garcia believes she has met her dream man, but her first date with him doesn't go exactly as she had expected.

The BAU and local authorities in Los Angeles investigate a series of brutal serial killings that appear to involve a famous comic book artist.

When one teenager is found murdered and her best friend is abducted in Chula Vista, California, the BAU must profile the killer and find him before he kills the other teen.

The BAU is called to West Bune, a small town in Texas, to investigate what appears to be spree killings that involve a teenaged boy.

After Prentiss and Reid go undercover in Colorado to investigate alleged child abuse at the compound of an underground cult in La Plata County, they are taken hostage when a federal raid on the fortress goes bad. Based on the case of Waco Siege.

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

The BAU investigates a series of murders in California's Central Valley that appear to be connected to a killer who jumps trains and chooses his victims based on their proximity to the railway.

When a narcissistic psychopath confesses he has killed seven people and more will die, the team must locate his latest victims before it is too late.

The BAU is called to assist local law enforcement in catching a serial killer, dubbed the "Road Warrior" by the media, who is shooting blonde women as they drive along freeways in Orange County, California. The case is complicated because the heinous acts appear to be at random and the shooter is described as looking normal. Meanwhile, JJ brings her new baby to the BAU headquarters to introduce him to the team.

When a young woman in an affluent community in Sarasota, Florida, disappears, the BAU suspects she may have been taken hostage by the partner of a pair of serial killers.

The mother of an abducted child works with the BAU in Olympia, Washington to identify a serial killer who kidnaps, murders, and embalms his victims.

The BAU investigates a series of deaths involving possible exorcisms in the Washington area that appear to be sanctioned by the Vatican, and SSA Emily Prentiss finds herself personally involved in the case.

The BAU travels to Boston when the serial killer from one of Agent Hotchner's first cases, which involved one of the most notorious murderers in the history of New England, returns after 10 years.

The BAU is called to Texas to investigate a serial killer who is targeting vacationing students on spring break on South Padre Island.

When a serial killer in Buffalo sends a videotape of one of his crimes to the BAU, the team discovers a message from the murderer that begs for help in stopping the killing.

The BAU responds quickly after a serial killer releases a new strain of a deadly anthrax virus in Annapolis that threatens the public and puts a member of the team at risk.

The BAU continues its search for a serial killer who has forced the team into Canada to catch him. Meanwhile, a team member may have become the target of a killer from the past.

Special Guest Star: C. Thomas Howell

While Rossi, Morgan, Reid and JJ profile a killer who is targeting an emergency room doctor and his son, Prentiss realizes that Hotch is missing.

The BAU is called to Louisville to help local authorities determine what caused a disturbed man to have a psychotic break at a pharmacy and murder several customers before fleeing the scene. The team must catch him before he kills anyone else.

The BAU is called to Los Angeles to investigate a series of killings that lead to a Goth rock star who appears to have become lost in the creepy alter-ego he portrays when he is on stage.

When The Reaper returns to Washington for a final showdown, the team works frantically to catch him before he reaches Hotchner's family.

As SSA Hotchner struggles with his return to work, the team is called to Atlantic City to profile a suspect with an unusual personal obsession: abducting certain types of women and turning them into real-life dolls.

The BAU profiles a child abductor who may have been harboring children for more than eight years.

The BAU profiles a highway serial killer, and Hotch interviews the victim's mother who might cross paths with the serial killer.

The BAU team travels to San Francisco to investigate the murders of several homeless men and teams up with a separate group of BAU operatives who are working another case they think is connected. This episode launches the Criminal Minds spin-off