Supernatural, a series about ghosts, ghouls, and pretty much everything else that goes bump in the night, is on average, these days at least, rarely scary.
During the show's maiden season, encountering a demon was a big deal, and angels, as is the case with most good vs. evil fiction, were believed to be a myth. Since then the show has built on its mythology tenfold with a five-season arc that revealed Heaven was indeed real while demons plotted to unleash Lucifer himself from his "cage" and onto the world. Thanks to a niche but loyal fan-base and a network (The CW) desperately in need of a stalwart, Supernatural avoided cancellation before seeing that arc through and became a big enough commodity for The CW to want it on their schedule for as long as humanly possible.
Basically, it's the new Smallville. Since what should've been its series finale, though, the show has devolved into the type of undead creature Sam (Jared Padalecki) and Dean Winchester (Jensen Ackles) might hunt. There are still great episodes and arcs here and there. But in the four seasons that have followed since the brothers defeated the Devil, the show unwisely tried to go bigger when returning to the lower albeit more personal stakes of the first three seasons would've been the smarter play. Some of the best recent episodes have favored quirky, winning black humor (sometimes excessively meta) rather than any scares.
Yet Supernatural wouldn't be turning the big 1-0 if it didn't deliver on its promise; also, so far the current season's been pretty solid. In the wake of bureaucratic angels and demons there are some legitimate episodes that shouldn't be watched with the lights off. As the show nears the 200-episode mark, revisit fifteen of its large crop that are actually scary.
"Unforgiven" (Season 6, Episode 13)
Just what kind of remorseless roguishness did Sam get into during the year he spent solo and soulless? The noir-esque "Unforgiven" forces Sam to confront his misdeeds when a series of murders draws him back to the same town where he worked a case during his dark period.
"Repo Man" (Season 7, Episode 15)
After seasons full of countless encounters with demons who amount to nothing more than easily dispatched foot soldiers, the refreshingly pared down "Repo Man" serves up a chilling reminder of the damage one demon can inflict on just one human when a spirit the Winchesters successfully exorcised years ago apparently returns to torment its former host body.
"Hello Cruel World" (Season 7, Episode 2)
Season seven ultimately doesn't come close to the series' highs, but it had a shot at its outset. The reason: a group of villains, the human-eating Leviathans, that didn't hail from Heaven or Hell. The shape-shifting, borderline indestructible monsters became tiresome but they made a grand entrance in "Hello Cruel World," invading a hospital and feasting on the patients—nothing enables fear of hospitals more than witnessing your doctor pig out the patients. When the Winchesters get sonned by one to the point of needing an ambulance, guess where they end up heading to.
"My Bloody Valentine" (Season 5, Episode 14)
Creature: Horseman of Famine
Gore doesn't always equal scares but starting this episode off with a couple eating each other does the trick. When Famine, one of Satan's horsemen, is revealed to be the culprit behind a town's inhabitants binging on their vices until death, the intensity ratchets up to ten. In the guise of a gaunt old man, Famine is the only genuinely unsettling horseman, and his visage is matched by Sam's addiction to demon blood, back in full force in the Famine's presence. The episode's title is a wink to Jensen Ackles' not-so-stellar attempt at horror on the silver screen, but there's room for self-deprecation when he's knocking it out of the park as he does during the hour's heavy final scene.
"The Kids are Alright" (Season 3, Episode 2)
Creepy kids: always a win. While Dean has a Maury moment when he returns to town to find a memorable fling now with a son that bears his likeness, he and Sam discover a changeling's been impersonating the children, killing fathers and locking mothers up to later devour.
"Of Grave Importance" (Season 7, Episode 19)
Creature: Various ghosts
"Haunted house" is an understatement when a lead from a fellow hunter sends the Winchesters to a manor populated with dozens of ghosts whose singular scariness pales in comparison to the house's Head Specter in Charge. Some of the novelty wears off when Sam and Dean's pseudo-dad turned ghost Bobby (Jim Beaver) gets stuck in the manor and uses the time to get a spirit tutorial. Besides that, though, the varying ghosts are all top-notch while the manor's proprietor proves to be a surprisingly formidable threat.
"Everybody Loves a Clown" (Season 2, Episode 2)
Correction: everybody loves a scary clown. The trope's well-worn but this homicidal Bozo, one who gasses kids to let him into their homes so he can eat their parents, is a horror layup.
"Croatoan" (Season 2, Episode 9)
Creature: Croatoan virus
Even if you don't watch Supernatural, you've almost definitely seen this one—since the series has been in syndication its become The One That Always Seems to Be On. A demonic viral outbreak traps the brothers and a few other survivors in a small building, and typical, but effective, close-quarters paranoia and mayhem ensues. Think a bargain budget but still memorable Dawn of the Dead.
"No Exit" (Season 2, Episode 6)
Creature: Ghost of H. H. Holmes
The brothers and de facto little sister Jo (Alona Tal) square off against the spirit of America's first serial killer, H. H. Holmes, who's up to his old tricks of abducting pretty blond women even in the afterlife. And guess who's just his type?
Creature: Lady in White
Duh, nobody's going to watch your show called Supernatural if the pilot itself doesn't meet the fear factor. This episode's ghost is no slouch, but it's the personal attacks on the Winchester men that bookend the episode—the inciting, and re-inciting incidents, if you will—that make us need every light on in the house while watching. A woman walks by her son's nursery and sees a man hovering over the crib...but her husband is currently asleep in front of the TV. A guy comes home, hears his girlfriend in the shower, and reclines on the bed for some much needed rest...until something starts dripping on him from above.
"Jump the Shark" (Season 4, Episode 19)
Never one to pass up meta, even self-skewering humor, Supernatural's creators own up to this episode's tongue-in-cheek title and present a new twist on the Winchester family history—a third son! Which would reek of story desperation if it didn't subvert typical shark-jumping tropes by using Sam and Dean's bastard brother as a narrative tool to reinforce their own sibling disconnect and Daddy issues. That all this family drama unfolds in the midst of a particularly dark case, as the brothers hunt a vengeful ghoul, doesn't hurt either.
"Family Remains" (Season 4, Episode 11)
Creature: Feral ghosts
Things take a decidedly non-supernatural turn when the spirits of an apparently haunted house turn out to be two feral flesh-and-blood siblings (the products of incest, typically). And, of course, a new wholesome American family just moved in despite Sam and Dean's warnings.
"Bloody Mary" (Season 1, Episode 5)
Creature: See title
In the early years Supernatural relied on basic horror myths/lore to pad its seasons out, which, when combined with basic WB/CW requirements (read: hot teens) made some episodes seem reminiscent of late '90s horror flicks. "Bloody Mary" is no exception, with the brothers squaring off against the infamous mirror ghost as it terrorizes a small town. When it's all over, the episode has one last creepy trick up its sleeve for the final scene, offering the first hints at the series' overarching mythology.
"Roadkill" (Season 2, Episode 16)
Creature: Vengeful spirit
You've seen this slasher before: a girl runs through the woods, her boyfriend is dead, and a sadistic dirty trucker-looking creep is hot on her heels. But Supernatural doesn't always need to be original when its catering to genre tropes at such a highly competent level as in the case "Roadkill." The episode takes place over the course of one night as the brothers try to vanquish a vengeful spirit on the only night of the year it haunts. Having fan-favorite sci-fi character actor Tricia Helfer guest as the requisite damsel in distress is the icing on the devil's cake.
"Skin" (Season 1, Episode 6)
First things first: don't watch this on Netflix. Supernatural's classic rock soundtrack is one of its best qualities and has been used to create some really memorable sequences during its run, but for whatever weirdo music rights reasons, "In-A-Gadda-Da-Vida" isn't on the streaming version. A shame, too, since it starts off what remains as one of this series' creepiest, most unsettling episodes. "Skin" plays like an hour of Criminal Minds with a horror twist, with the Winchesters investigating several accusations of men murdering their loved ones. The villain's motive and nature are genuinely disturbing, but the highlight is a nasty shape-shifting scene.