In most episodes of Star Trek and its various spin-offs, members of Starfleet approach the unknown not with a sense of fear but with hope and optimism, confident that any threat can be overcome with empathy and logic.
But that doesn’t prevent writers from testing these bold explorers of the future with some scary episodes.
Over more than 60 years of existence, Star Trek has dabbled in horror, creating these twenty-five eerie episodes.
1. “Catspaw” (The Original Series, Season 2, Episode 7)
Thanks to the need to reuse sets around the studio lot, the original series of Star Trek sent the Enterprise to some pretty mundane locations, including planets that looked just like 1930s Chicago or ancient Greece. That versatility served the show well when they made “Catspaw,” written by Robert Bloch, author of the novel Psycho.
With its haunted castle and cackling witches, “Catspaw” feels more like a gothic horror movie than a space exploration show. But the cast throws them into the story, making “Catspaw” one of the best spooky Trek episodes.
2. “Calypso” (Short Treks Season 1, Episode 2)
As their title suggests, Short Treks are 10-15 minute long episodes that allow filmmakers to tell different types of stories within the Star Trek universe. With “Calypso,” writer Michael Chabon and director Olatunde Osunsanmi tell a creepy tale about a man called Craft (Aldis Hodge) who gets pulled aboard the USS Discovery only to find it deserted.
As Craft makes his way through the ship, he learns just how vast the emptiness of space can be.
3. “Empok Nor” (Deep Space Nine Season 5, Episode 24)
Deep Space Nine, the most complex of the Star Trek series, featured characters who embraced moral shades of gray. That was most true of Garak, the Cardassian whose espionage past belied his claims to be nothing more than a plain, simple tailor. That hidden history comes to the fore in “Empok Nor,” in which Garak accompanies Chief O’Brien and a Federation crew to investigate an abandoned space station.
As madness overcomes the characters, “Empok Nor” pushes them to their paranoid limits, forcing them to reconsider their core values.
4. “Remember Me” (The Next Generation Season 4, Episode 5)
In “Remember Me,” Doctor Beverly Crusher finds fellow members of the Enterprise-D crew disappearing from memory. Even trusted leaders such as Captain Picard treat Crusher like she’s crazy when she talks about her beloved son Wesley. Of course, the episode connects the mystery to a space anomaly, which gets solved through ingenuity and quick thinking by the end of the episode.
But for most of its running time, “Remember Me” captures the horror of isolation, thanks to Gates McFadden’s outstanding performance.
5. “Impulse” (Enterprise Season 3, Episode 5)
Vulcans love to correct people, especially people who suggest that green-blooded people have no emotions. Vulcans experience emotions with greater intensity than even humans, but they suppress them. At least, they stop them until something overrides their constraints, as happens in the Enterprise episode “Impulse.” When the NX-01 rescues a Vulcan ship in distress, they encounter a crew so overcome with anger that they act like rage zombies.
Captain Archer and his crew fight to find a cure before the same illness overtakes his Commanding Officer, T’Pol.
6. “Q Who” (The Next Generation Season 2, Episode 16)
Some may argue that overexposure has stripped the Borg of their menace. Still, even the most cynical viewer feels a chill run down their spine when the assimilating aliens first appear in The Next Generation’s second season.
When the godlike being Q grows tired of Picard’s refusal to accept his help, he whisks the Enterprise to deep space so they can see a threat they’ve never experienced before.
7. “Darkling” (Voyager Season 3, Episode 18)
Although moody at times, the Doctor performed his duties with a smile and a song in his heart. At least until his programming went haywire, as in “Darkling.” When the Doctor starts uploading personalities of historical figures into his matrix, an unexpected side-effect occurs. A darker, evil identity emerges, one that threatens Voyager and its crew.
Trek has played with similar concepts, including the original series episode “The Enemy Within.” But “Darkling” indulges in the horror of the Doctor’s alternative personality, earning its position on this list.
8. “Frame of Mind” (The Next Generation Season 6, Episode 21)
Like “Remember Me,” the season six episode “Frame of Mind” delves into psychological horror, this time focusing on Commander Riker. After being captured, Riker begins having strange hallucinations, undermining his grasp on reality. Viewers familiar with the Christopher Nolan movie Inception might find the story familiar.
Still, there’s no denying the raw desperation William Frakes brings to Riker as he tries to understand his predicament.
9. “Context Is for Kings” (Discovery Season 1, Episode 3)
As one of the best sci-fi movies of all time, the James Cameron film Aliens casts a long shadow over the genre. So it’s no surprise that Star Trek would borrow the movie’s tone, first in the Voyager episode “Macrocosm” and then in “Context is for Kings” on Discovery. Upon learning about a horrible accident on the USS Glenn, the Discovery’s Captain Lorca sends Michael Burnham and a rescue crew to investigate.
Episode director Akiva Goldsman recasts Aliens in Federation guise as Burnham and her fellow explorers fight their way through a darkened ship against a monster they cannot see.
10. “Phantasms” (The Next Generation Season 7, Episode 6)
In the same way that scary movies sometimes indulge in silly plots, so also do creepy Trek episodes get a bit goofy. Take the Next Generation episode “Phantasms,” in which the android Data begins experiencing surreal dreams. In one of these dreams, he finds Troi transformed into a birthday cake.
In another, Data gets dismembered. Although few would find these nightmares conventionally frightening, the absurd situations create a sense of unease.
11. “Wolf in the Fold” (The Original Series Season 2, Episode 14)
None of the original series crew members could match engineer Montgomery Scott for pure affability. So, viewers' hearts sink when the camera finds Scotty standing over a dead young woman with a knife in his hand.
Another Robert Bloch-penned episode, “Wolf in the Fold,” connects an alien entity to Jack the Ripper, an entity that takes hold of beloved Mr. Scotty.
12. “The Adversary” (Deep Space Nine Season 3, Episode 26)
Throughout the first three seasons of Deep Space Nine, Commander Sisko and his crew learn about a powerful enemy called the Dominion. In the season three finale, “The Adversary,” Sisko discovers that the Dominion involves shape-changers like his security officer Odo, one of whom has infiltrated the crew.
In a plot that recalls the John Carpenter classic The Thing, Sisko and Odo must perform blood tests to find the shapeshifter before paranoia overtakes them.
13. “Hegemony” (Strange New Worlds Season 2, Episode 10)
In its first season, Strange New Worlds made the Gorn far more menacing than the rubber-suit creature that first appeared in the original series episode “Arena.” The season two finale, “Hegemony,” builds upon the Gorn threat implied in that previous episode by unleashing a whole army of creatures on a planet modeled after 20th-century Earth.
The sight of reptilian monsters destroying playgrounds and leading street shops gives “Hegemony” a surprisingly dark tone, something that an appearance by young Montgomery Scott cannot even dispel.
14. “The Devil in the Dark” (The Original Series Season 1, Episode 25)
Many of the first Star Trek stories featured the Enterprise encountering an unknown lifeform, initially inspiring fear and hatred. That’s the case in “The Devil in the Dark,” in which Kirk and Spock investigate a creature killing miners on a distant planet. The cast does admirable work selling the menace of the cheap-looking monster they encounter.
This sets up a satisfying conclusion, one of the best examples of the franchise’s commitment to empathy and understanding.
15. “The Haunting of Deck Twelve” (Voyager Season 6, Episode 25)
Few characters have experienced a redemption arc like Neelix, the cook and guide aboard the starship Voyager. Initially introduced as an annoying creep, Neelix becomes a kind and empathetic figure, as shown by the care he gives to a group of kids rescued by the Borg. When a nebula knocks out Voyager’s power, Neelix comforts the kids by telling a spooky ghost story.
“The Haunting of Deck Twelve” won’t give any nightmares to viewers, but it does feature plenty of old-school chills.
16. “The Man Trap” (The Original Series, Season 1, Episode 1)
The first episode of Star Trek to hit TV screens, “The Man Trap,” introduced viewers to Kirk and McCoy with a fun monster tale. Kirk accompanies McCoy to visit his one-time betrothed, now married to another man. The visit turns deadly when men keep dying around the settlement, leaving behind bodies sucked dry of their sodium.
As the Enterprise crew investigates the source, McCoy realizes the woman he once loved is not all he remembers.
17. “The Quickening” (Deep Space Nine Season 4, Episode 24)
Star Trek presents Starfleet members as the best of the best, the brightest, and most capable minds from Federation planets. Even by those standards, Deep Space Nine’s Doctor Bashir stands out, thanks to his genetically engineered improvements. That level of excellence increases the terror of the plague that Bashir encounters in the Deep Space Nine episode “The Quickening.”
As Bashir, along with Kira and Dax, fight to find a cure for the disease, tearing apart a nearby planet, they discover the limits of their abilities, forcing them to accept that no amount of training or brilliance can save them from some diseases.
18. “The Thaw” (Voyager Season 2, Episode 23)
When “The Thaw” aired in 1996, Stephen King’s It and Killer Klowns from Outer Space introduced creepy clowns into the popular consciousness. So when Harry Kim and B’Elanna Torres get their consciousnesses stuck in a computerized nightmare, they encounter several unsettling figures, including an evil clown.
Played by Spinal Tap and Better Call Saul legend Michael McKean, the Clown may come off as more silly than scary, but there’s no denying the threat he and others pose to Kim and Torres.
19. “I, Excretus” (LWD Season 2, Episode 1)
As much as the holodeck opened Trek to different storytelling genres, the franchise did not often use holograms for scary stories. And, to be fair, “I, Excretus” isn’t explicitly a scary story either, despite the involvement of the Borg. After all, it comes via Lower Decks, the animated series that pokes loving fun at Trek’s absurdities.
However, as Ensign Beckett Mariner goes through various holodeck simulations, she witnesses sights that neither she nor the viewers will soon forget.
20. “Conspiracy” (The Next Generation Season 1, Episode 25)
Even the most devoted Trekkie knows that the first season of The Next Generation had more misses than hits. Part of the show’s learning curve involved doing away with a more extensive plot line involving a conspiracy among high-ranking Federation officials. Picard and Riker get to the source of the problem in the aptly-titled season finale, “Conspiracy.”
In a shocking and gory moment for the show, the duo blasts the head off of a nasty Starfleet officer to reveal a mind-controlling worm inside. The storyline gets dropped after that episode, never to be mentioned again, but no one who saw “Conspiracy” can forget that disgusting little bug.
21. “The Assignment” (Deep Space Nine Season 5, Episode 5)
In addition to its moral ambiguity, Deep Space Nine explored spirituality more than any other Trek series. Commander Sisko becomes the Emissary of the Prophets, alien beings living inside a nearby wormhole and worshiped by Bajorans. They also meet the Pah-Wraiths, evil counterparts to the Prophets who can possess their victims, including Chief O’Brien’s wife Keiko.
“The Assignment” turns Keiko into an evil, red-eyed monster who torments poor O’Brien (a regular occurrence on the show, to be honest) and demonstrates the enormous power he and Sisko must face.
22. “Vanishing Point” (Enterprise Season 2, Episode 10)
Set more than a century before the original series, Star Trek: Enterprise got a lot of mileage out of characters’ early encounters with technology standards in other series. Such is the case for the season two episode “Vanishing Point,” in which the transporter goes wrong for communications officer Hoshi Sato. After her accident, Hoshi starts phasing out of reality, essentially becoming a ghost.
Episode director David Straiton forgoes the easy route of making Hoshi haunt the NX-01 and instead deals with the horror of her fading existence, making “Vanishing Point” a terrifying counterpoint to “Remember Me.”
23. “Schisms” (The Next Generation Season 6, Episode 5)
Despite all the fantastic technology available on the starship Enterprise, its crew still suffered many of the same ailments as modern-day citizens, including nightmares. Of course, when humans have nightmares in deep space, they become more unnerving and strange.
That exponential factor drives “Schisms,” in which shared nightmares lead Riker, LaForge, and others to learn that an alien force has been abducting and experimenting on them in their sleep.
24. “Night Terrors” (The Next Generation Season 4, Episode 17)
If dreams are challenging for humans on Enterprise-D, imagine how worse they are for the ship’s resident Betazoid, Counsellor Deanna Troi. As an empath, Troi can feel the emotions of others, which makes her vulnerable to both experiencing and transmitting those sentiments.
So when a traumatized Betazoid comes aboard the Enterprise in “Night Terrors,” he and Troi broadcast horrors to the entire ship, forcing the never-sleeping Data to save the day.
25. “Stardust City Rag” (Picard Season 1, Episode 5)
On the one hand, “Stardust City Rag” is the most light-hearted episode of Star Trek: Picard, the sequel series that indulged in grimness for two seasons before becoming a delightful reunion show in its third season. Conversely, “Stardust City Rag” also opens with a ghastly sequence in which Icheb, the young ex-Borg adopted by Seven of Nine in Voyager, gets dissected alive.
The scene clashes with the caper that takes up the rest of the episode but also leaves the viewer unsettled.
