Criminal Minds may be coming back in a Paramount+ revival, but the long-running CBS series has certainly left an impression on audiences. Some of those impressions, however, were a lot more horrifying than others. After all, when a series is about the worst of humanity, then it's no surprise when episodes can turn into a mini horror movie.

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The BAU team and their strong personalities captured the hearts of fans, making it that much more horrifying when someone from the main cast was put in danger. The show wasn't afraid to push the envelope and brought more bone-chilling storylines than the next with each new season. Here's a look at some of the darkest and scariest episodes of Criminal Minds throughout the series.

"North Mammon" (Season 2, Episode 7)

A young girl watching tv in Criminal Minds

This episode has the plotline of a horror movie as three friends on the soccer team are abducted by a sick individual who uses them to play a twisted game. The unsub tells the girls that two of them can survive, but must choose one to die. Different from many episodes that focus on the BAU team, this one focuses mostly on the victims who are trapped in an underground cellar.

One girl is sick and getting weaker by the day as they're trapped without food or water, and the two other friends decide she's the one who must die. In an ultimate twist, the unsub throws down a hammer upon their decision, telling them they have to kill her, and demonstrates to viewers what lengths someone would go to survive.

"Revelations" (Season 2, Episode 15)

Two police officers walking in Criminal Minds

It's no secret that Dr. Spencer Reid looked into the face of evil numerous times throughout the show, his intelligence level making him a target to many unsubs. He quickly became a fan favorite, making the moment he's first found in a life-threatening situation a nail-biting episode for many. He gets kidnapped by Tobias Hankel, a devoutly religious man with multiple personality disorder.

Viewers watched as the BAU team raced to find him, switching between Spencer being tortured, and flashbacks from Spencer's past that were induced by the kidnapper's concoction of Dilaudid cut with a psychedelic. Between the graphic scenes, the lovable main character in danger, and the acting of James Van Der Beek as the unsub, this episode is sure to give any viewer the heebie-jeebies.

"Fear and Loathing" (Season 2, Episode 16)

A Black man in Criminal Minds

This episode is just as important as it is horrifying as it tackles the topic of racism. Several women of color have turned up murdered and the town believes it's the act of a hate crime. The BAU brings controversy as they say the signatures aren't that of a hate crime as they're sexually motivated and believe that the killer is a person of color himself.

Shortly after the announcement is made of the profile, Detective Ware is shot by a white man who believed him to be a threat just because of his skin color. The episode is tragic as Derek Morgan had just talked moments before the shooting with the detective about wishing race wasn't such an issue and people were judged by character instead.

"Scared To Death" (Season 3, Episode 3)

A scared looking boy in Criminal Minds

Reminiscent of the 1980 psychological horror film Phobia, this episode featured a psychiatrist using his patients' fears against them. Flashbacks from the psychiatrist's childhood provided an insight into how this came to be, having been abused by his mother throughout his formative years.

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There are multiple times the viewers watch as the therapist lures his victims and kills them utilizing drowning, burying them alive, or suffocating them with the illusion that he's trying to treat them of their anxieties. Having an unsub as someone people are supposed to trust makes for an episode that has viewers second-guessing who they confide in after watching.

"Penelope" (Season 3, Episode 9)

Kevin Lynch in Criminal Minds: Penelope

The previous episode leaves everyone in shock as Penelope Garcia was shot by a man who asked her on a date. The tension at the beginning of "Penelope" is similar to a medical drama as viewers watch with bated breath as surgeons try to save her. Thankfully she survives, but then becomes suspended as it's revealed she may have been keeping a secret from the BAU team which ultimately put her and other lives in danger.

After telling Derek the guy who shot her was the one she went on a date with, she becomes upset at the fact that the attractive man wasn't interested in her. The episode is a tightly wound one as Penelope hacks the FBI's system to uncover why the man chose her as a target.

"Birthright" (Season 3, Episode 11)

A couple looking confused in Criminal Minds

A string of young women are found murdered after being mutilated and burned. As the investigation unravels, the BAU discovers an eerie connection to similar killings that happened in the 1980s. The plot in this episode bends and twists as the BAU struggle to identify who the copycat serial killer is, as the original murderer had been dead before the first girl was even killed.

They make the horrifying discovery that his son, created by an act of evil on one of his captors, found out who his father was and decided it was his birthright to continue on the horrible legacy. This episode features many disturbing scenes where they show the women being tortured which makes for a hard watch.

"Zoe's Reprise" (Season 4, Episode 15)

A young man talking in Criminal Minds

The parallels to real-life serial killers and the tragic after story to one of the actors make this episode stick out as a frightening one. Rossi is approached by a criminology student, Zoe Hawkes, after one of his book readings and she tells him she believes the string of killings happening in her hometown is the work of one person, although each murder is done differently. The BAU eventually discover that Zoe was correct and the connection of the killings is that they were all inspired by serial killers including BTK, Son of Sam, and Jack the Ripper.

Shockingly, Johnny Lewis, the actor of the unsub, sustained brain damage a few years after the episode aired, resulting in a tragedy where it’s speculated he killed his landlady before jumping to his death (per News Daily)

"To Hell..."&"...And Back" (Season 4, Episodes 25 & 26)

A dead pig in Criminal Minds

The season four finale featured two emotional episodes. After a series of transients and sex workers go missing, a war veteran acting as their protector tries making the police aware there's a serial killer amongst them. The police turn their heads the other way, not caring for their welfare.

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The episode switches points of view and shows a horrifying moment as the killer chops up bodies and feeds them to his pigs. It's revealed that Lucas, an adult male, had the mental equivalent of a young child and was being manipulated by his brother, Mason Turner. The episodes are not for the faint of heart.

"Mosley Lane" (Season 5, Episode 16)

Three children looking in the same direction in Criminal Minds

Young children have been going missing in public areas, never to be seen again. It's revealed that the unsub is two people, a wife and husband duo, who work together to abduct their victims. Anita and Roger Roycwood are two of the most twisted suspects the BAU team has ever seen, knowing they turned to abduct children after not being able to have their own.

In a horrifying scene, Anita Roycewood sings a nursery rhyme to a child sleeping in a box, and pushes it into their family's crematorium, burning the boy alive. The episode is chock-full of terror and realism, children abductions prevalent in true crime to this day, and the acting provided by the unsubs and the victims makes for one of the scariest episodes of the shows running.

"Our Darkest Hour" (Season 5, Episode 23)

A man with his back to the camera in Criminal Minds

The element of fear is enhanced in this episode by using two things: rolling blackouts and actor Tim Curry, the original Pennywise, as the unsub. Garcia discovers that the series of rapes and murders occurring throughout the Los Angeles area have been going on for over 26 years, always under the cover of blackouts, and up until now have never been connected.

Horror fans appreciated the acting of Tim Curry in this episode, knowing he was familiar with the genre, and the creepiness of the serial killer he plays translates that. It's reminiscent in many ways of the popular miniseries. He took to the dark sewers to lure his victims, the killer in "Our Darkest Hour" finds familiarity in the cover of darkness.

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