A.J. Cook and Paget Brewster were fired after the fifth season. According to Brewster, CBS did this to save money. Brewster was suddenly brought back for the sixth season but her character was written out towards the end of the season. Cook was replaced with Rachel Nichols. Brewster was rehired for the seventh season as she still had a season left on her contract. Cook signed a new contract to return and Nichols was fired. Brewster left after the seventh season because she did not like how CBS treated her.
The character of Special Agent Reid was a child prodigy, having graduated from high school at the age of 12. Matthew Gray Gubler, describing what may form his character's genius, has said that Reid may have Asperger's syndrome and perhaps even be mildly schizophrenic. Reid's mother was schizophrenic herself.
When David Rossi (Joe Mantegna) joins the team, he makes a comment that their offices are better than "that bunker" the BAU used to work out of. The comment isn't metaphorical. The actual BAU (in its many earlier incarnations and titles) used to operate out of a bunker former FBI Director J. Edgar Hoover had built below FBI headquarters in Quantico, VA.
In a 2012 interview in New York Magazine, Mandy Patinkin said that he greatly regrets ever having accepted his role on "Criminal Minds": "The biggest public mistake I ever made was that I chose to do Criminal Minds in the first place. I thought it was something very different. I never thought they were going to kill and rape all these women every night, every day, week after week, year after year. It was very destructive to my soul and my personality. After that, I didn't think I would get to work in television again. I'm not making a judgment on the taste [of people who watch crime procedurals]. But I'm concerned about the effect it has. Audiences all over the world use this programming as their bedtime story. This isn't what you need to be dreaming about. A show like Homeland [on which Patinkin began appearing in in 2011] is the antidote. It asks why there's a need for violence in the first place."
In the time between Lola Glaudini's departure from the show and Paget Brewster's arrival, footage is used in the opening credits that originally featured Glaudini. The footage, from episode 1.03, is digitally altered so that Glaudini does not appear.
One of the signature images of this show is the brief shot of a business jet flying the team to a crime scene. Often these shots are paired as book-ends at the beginning and end of an episode, with voice-over of a cast member reciting a famous quotation. The jets shown are always Gulfstream products, including models G-IV, G-V, and G-450. Occasionally the shots are reversed left-to-right (e.g., episodes "A Thin Line" and "I Love You, Tommy Brown"). The tail numbers shown are often registered to Gulfstream Corporation, indicating that the shots are taken from Gulfstream publicity materials.
CBS aired an episode after Super Bowl XLI (2007) in the hopes of transforming the series from a relatively modest hit into a top ratings performer. The episode featured cameos by Super Bowl announcers Jim Nantz and Phil Simms.