The sixth season of Criminal Minds premiered on CBS on September 22, 2010 and ended May 18, 2011.
Before the filming of the season began, it was announced that A. J. Cook had been let go from the series, reportedly due to budget cuts on the show relating to the launch of the Criminal Minds spinoff.[1] Thanks to letters and petitions by fans, Cook was allowed to return for the first two episodes to wrap up her character's storyline.[2] She later returned as a special guest star in two subsequent episodes of this season.[3][4]Paget Brewster was a regular for eighteen episodes and was let go from the series as well.[5]Rachel Nichols appeared as a guest star for two episodes and was then promoted as a regular, but her contract wasn't picked up after the season finale.[6]
The opening sequence changed this season: more sound and visual effects were added; the theme song itself was amplified, and an electric guitar part was added.
In the season premiere "The Longest Night", Tim Curry reprised his role as one of the series' most notorious criminals, Billy Flynn, also known as "The Prince of Darkness". Robert Davi reprised his role as Detective Adam Kurzbard, who led the investigation of the murders. In the episode "J.J.", Chris Marquette guest-starred as James Barrett, a man who abducted and attempted to murder Kate Joyce. In the episode "Remembrance of Things Past", Daniel J. Travanti guest-starred as Lee Mullens, a serial killer who suffers from Alzheimer's disease. In the episode "Compromising Positions", Craig Sheffer guest-starred as James Thomas, an impotent serial killer who murders married couples.
In the episode "Safe Haven", Sterling Beaumon guest-starred as Jeremy Sayers, a juvenile delinquent and family annihilator who has been hated by his mother ever since he was born. Mare Winningham guest-starred as Nancy Riverton, a mother who allows Jeremy to stay in their home for the night. In the episode "Devil's Night", Leonard Roberts guest-starred as Kaman Scott, a disfigured serial killer who burns his victims alive during Devil's Night, the notorious pre-Halloween celebration. In the episode "Middle Man", Steve Talley, Michael Grant Terry, and Jake Thomas guest-starred as Michael Kosina, Christopher Salters, and Scott Kagan, aka "The Johnson County Brotherhood", a trio of serial rapists and killers who abduct exotic dancers. Melissa Claire Egan guest starred as Tara Dice, an exotic dancer who is questioned by Prentiss and Reid.
In the episode "Reflection of Desire", Robert Knepper guest-starred as Rhett Walden, also known as "The Hill Ripper", a schizophrenic abductor who idolizes the movie Reflection of Desire, a film his deceased mother starred in. Sally Kirkland guest-starred as May Walden, a famous actress from Hollywood's Golden Age who, because of her pregnancy, made only one motion picture, and her career was ruined afterwards. Whitney Able guest-starred as Penny Hanley, a woman Walden abducts after Kelly Landis' murder. In the episode "Into the Woods", Gattlin Griffith guest-starred as Robert Brooks, a young boy who is abducted and raped by Shane Wyland. Emily Alyn Lind guest-starred as Anna Brooks, Robert's younger sister who is also abducted by Wyland.
In the episode "What Happens at Home...", Kenneth Mitchell guest-starred as Drew Jacobs, a serial killer who murders several women, including his own wife. Madison Leisle guest starred as Jacobs' daughter, Heather. In the episode "25 to Life", Kyle Secor guest-starred as Donald Sanderson, a man who was framed and imprisoned for the murder of his family, and Philip Casnoff guest-starred as James Stanworth, the man responsible for framing Sanderson and murdering his family. Angus Macfadyen guest-starred as Sean McCallister, Emily Prentiss' former boss at Interpol who is murdered by one of the series most notorious criminals, Ian Doyle, played by Timothy V. Murphy. In the episode "The Thirteenth Step", Jonathan Tucker and Adrianne Palicki guest-starred as Raymond Donovan and Sydney Manning, two young lovers who go on a killing spree.
In the episode "Today I Do", Rebecca Field guest-starred as Jane Gould, a stalker and abductor who acts as a caretaker so she can be appreciated. Rachel Miner guest-starred as Molly Grandin, a woman who Gould abducts and holds captive in her house. In the episode "Coda", Lew Temple guest-starred as Bill Thomas, a man who abducts the parents of Sammy Sparks, a boy who has autism. Mimi Kennedy guest-starred as Sammy's social worker Miss Rogers. In the episode "Lauren", Patrick Fischler guest-starred as Jack Fahey, an Irish mobster and an associate of Ian Doyle. In the episode "With Friends Like These", Bug Hall guest-starred as Ben Foster, a schizophrenic spree killer who, after burning down a church, begins hallucinating three people who died there.
In the episode "Hanley Waters", Kelli Williams guest-starred as Shelly Chamberlain, a spree killer who is unable to come to terms with the death of her son, who died in a car crash. In the episode "Out of the Light", Jeffrey Meek guest-starred as Robert Bremmer, a serial killer who raped his stepdaughter, Rose, and began abducting, raping, and murdering women who resemble Rose. In the season finale "Supply and Demand", Angela Sarafyan guest-starred as Lucy, the leader of a human trafficking ring who poses as one of the victims. Amy Price-Francis guest-starred as Supervisory Special Agent Andi Swan, the Unit Chief of the Domestic Trafficking Task Force and Sarah Foret guest-starred as Renee Matlin, an FBI undercover agent who is held captive within the ring.
With Detective Spicer dead, Los Angeles still suffering from citywide blackouts, and the "Prince of Darkness" (Tim Curry) still at large, the BAU juggles tracking him down and rescuing Spicer's daughter.
When a Maryland teenage girl goes missing and the prime suspects pass a polygraph test despite being the last people to see her alive, the BAU juggles extracting a confession and dealing with the missing girl's overprotective parents. Meanwhile, JJ contemplates a major job promotion that threatens to take her away from the team.
When two Bristol, Virginia, women are tortured, sodomized, and fatally electrocuted, the BAU sets out to determine whether or not the crimes were committed by a prolific serial killer (Daniel J. Travanti) who murdered twenty women over the course of nine years and was never caught.
When two Akron, Ohio, couples are killed after being forced to have sex, the BAU sets out to track down a killer attempting to compensate for his own impotence. Meanwhile, Garcia volunteers to take over the still-vacant role of communications liaison.
When two Midwest families are killed in their homes, the BAU attempts to track down a psychopathic adolescent with a desire to punish matriarchal figures. Meanwhile, Morgan receives an unexpected visit from a former acquaintance.
When the latest in a series of deadly pre-Halloween arson attacks takes place in Detroit, Michigan, the BAU sets out to profile and track down a serial killer bent on exacting vengeance against the people who destroyed his life.
When three Indiana exotic dancers are abducted, raped, and killed after being held captive for two days, the BAU juggles profiling a three-person killing team and rescuing their latest kidnapping victim.
When a missing Washington, D.C., woman is found with her lips cut off and a mysterious piece of paper stuffed down her throat, the BAU sets out to track down a budding abductor who forces his victims to reenact a scene from a 1950s film. Meanwhile, Garcia attempts to help the team identify the killer by exposing a piece of her personal life.
When a missing ten-year-old boy is found dead on the Appalachian Trail and a brother and sister subsequently go missing, the BAU sets out to apprehend a pedophilic child killer responsible for the deaths of eight children.
When three Las Cruces, New Mexico, women are strangled to death, the BAU recruits FBI cadet Ashley Seaver (Rachel Nichols) to help them identify the serial killer hiding among a gated community's residents. Meanwhile, the team uncovers a dark secret about one of their own.
With Hotch taking time off to commemorate the anniversary of Haley's death, the remaining members of the BAU set out to determine whether or not a paroled murderer committed the crime he was charged with. Meanwhile, Prentiss approaches Rossi with an unusual request involving Seaver's remedial training.
When three Miami, Florida residents are found dead in their homes, the BAU determines the killer is obsessed with completing a specific ritual found in Afro-Caribbean religions. Meanwhile, Reid calls his well-being into question after starting to suffer prolonged headaches and hallucinations.
When two mass shootings at two separate Montana gas stations claim the lives of fourteen people, the BAU juggles profiling a newlywed couple and preventing them from embarking on a killing spree. Meanwhile, Prentiss receives disturbing news about a ghost from her past.
The BAU returns to Los Angeles, California, to determine a serial killer's bizarre agenda after three women are abducted, drowned in methanol, and found with a piece of skin removed from their right foot. Meanwhile, Morgan notices a drastic change in Prentiss's behavior.
When a Syracuse, New York, undergraduate student goes missing and her disappearance is connected to a four-month-old cold case, the BAU sets out to profile a sadistic serial killer who sees themself as a motivational coach. Meanwhile, Prentiss grows increasingly concerned after receiving an update from her former Interpol colleagues.
When a Lafayette Parish, Louisiana, couple goes missing and their autistic son walks into school covered in blood, the BAU juggles profiling a kidnapper who personally knew the abductees. Meanwhile, Prentiss's clandestine mission to track down her Interpol team's greatest enemy reaches an earth-shattering climax.
When two Washington, D.C., families are found dead from apparent murder-suicides and an ambush threatens two of their own, the BAU sets out to catch an international criminal (Timothy V. Murphy) determined to fulfill a sinister agenda. Meanwhile, Prentiss struggles to keep her past a secret from the rest of the team.
When Prentiss disappears following the death of a former Interpol colleague, the BAU reunites with JJ in an attempt to learn more about their missing colleague's past relationship with terrorist Ian Doyle and the series of events that led to his capture eight years earlier.
With Prentiss dead and Seaver officially an FBI agent and team member, the BAU sets out to determine whether or not a killing team with a pack mentality is responsible for the murders of two Portland, Oregon, residents. Meanwhile, Reid becomes emotionally involved after an unexpected twist changes the course of the investigation.
When a mass shooting at a Tampa, Florida, gun store claims the lives of four people, the BAU attempts to profile a budding spree killer determined to take down a specific target. Meanwhile, Hotch interviews each individual team member about their feelings regarding the loss of Prentiss.
When three San Diego, California, college students are stabbed to death in their off-campus homes, the BAU sets out to track down a stalker-turned-serial killer who targets women resembling a face from his past. Meanwhile, Hotch comes under scrutiny after Section Chief Strauss starts reviewing the team's grief assessment forms.
When a North Carolina woman's injuries are consistent with those found on an unidentified corpse discovered three years earlier, the BAU juggles profiling a sexual sadist and determining whether or not there are other victims.
When a Jacksonville, Florida, pumping crew discovers twelve sets of skeletal remains buried in a mass grave, the BAU sets out to establish a connection between the victims and the killer. Meanwhile, Morgan becomes personally involved in the case after his aunt arrives in Florida with suspicions that her missing daughter is among the dead.
When two missing persons are found dead in the trunk of a dead man's car, the BAU works with SSA Andi Swan (Amy Price-Francis) and the FBI's Domestic Trafficking Task Force to take down a human trafficking organization. Meanwhile, Hotch warns the team of possible restructuring and a familiar face makes an unexpected decision.