The Worst Thing Linda Barnes Did On Criminal Minds
Not every antagonist on "Criminal Minds" is a serial killer. Sometimes the very worst opponents the BAU team has ever faced have been on the same side of the law. The tight-knit team of investigators have faced many challenges over the series' 15 seasons, but one character not only managed to stymie the team at every turn but see the BAU team split up, and Rossi (Joe Mantegna) forced into early retirement. That character is Linda Barnes (Kim Rhodes), who took over as the BAU's supervisor at the beginning of Season 13.
While a capable leader in some respects, with a talent for restructuring the units under her purview to maximize their efficiency, Barnes is first and foremost a political animal: She doesn't do the things she does to help catch killers, she does what she does to gain political power in her quest to become director of the FBI. In the course of her tenure at the BAU, she did some truly heinous things, but let's talk about the absolute worst.
The exact wrong call at the exact wrong time
In the Season 13 episode "Annihilator" Barnes volunteers the BAU team to investigate a murder in St. Louis not because of any innate desire to help, but because she believes the case will be easy to solve and provide the team with good optics. Despite not being a profiler herself, she invites herself along and begins assigning BAU members to specific avenues of investigation, despite having named JJ as the acting lead in the field. As the case progresses, she becomes convinced that a man named Larry is the killer, and when Larry is found dead of an apparent suicide, she's convinced the case is closed. Tara (Aisha Tyler) and JJ quickly work out the suicide note is faked, however.
The team managed to find the killer, who is cornered at an airport and threatening suicide unless a witness they have in custody (a woman the killer is obsessed with) is brought to him. Despite the fact that it's obvious the killer is planning something, Barnes brings the woman to the scene in an attempt to pacify the killer, who instead attempts to shoot the civilian. The civilian survives, thanks to a bulletproof vest, but his attack forces the BAU team to have to put the killer down rather than arrest him.
From bad to worse
Instead of acknowledging the mistake, Barnes doubles down, blaming the BAU for being too slow, and finding JJ's leadership incompetent (despite having placed JJ into the leadership role). As a result, she successfully obtains the FBI Director's permission to disband the BAU, reassigning everyone apart from Alvez (Adam Rodriguez) and Simmons, with JJ acting as conditional unit chief, having to run every decision through Barnes. She also forces Rossi into early retirement.
While the status quo for the series gets restored in short order (quite literally in the following week's episode), it should be noted that Linda Barnes is easily one of the most formidable antagonists the "Criminal Minds" team ever faced. Unlike the killer of the week, Barnes couldn't be sent to jail by the episode's ending; she was the boss. An incredibly unlikable, awful boss, who for one brief moment did what no other antagonist on the show could: effectively destroy the BAU.