In 1954, young Billy jumps into the newly opened school swimming pool. He grimaces at a sudden noxious stench. From beneath, an unseen hand grabs him and wrenches him beneath the water. He breaks to the surface and screams for help. From the office, lifeguard Charlie, having been fooling around with Billy's older sister Cindy, leaps into the water...
Forty-two years later, in a smoke-filled Chemistry classroom, a model volcano spits small explosions. Zeke, the volcano's builder, apologises for his slight miscalculation.
Greta asks Zeke what went wrong. Mixing manganite with water, says Zeke, is always combustive - he just miscalculated the ratio. As the class disperses, Zeke gingerly approaches Clorice: being on the swim team, she might be interested in his recent find. She agrees to meet him tomorrow, 7:30, at the gym.
...
In the boy's changing room, behind a locker, is a door marked "TO POOL". In a dim hall, a huge black sheet covers a disused swimming pool. It opened briefly in the 1950s, before a surprisingly swift closure. Thrilled, Clorice decides to lobby for its re-opening. As the two leave, caretaker Charlie, having secretly followed them, casts a wary eye at the pool. In the black sheet rises a human-shaped bulge...
Weeks later, the swim team have their very own pool. During a practise session, Clorice and Greta swim to the edge. At a strange, severely unpleasant smell - the pipes must still be dirty- Greta climbs out. As Clorice follows, something vainly lunges for her ankles...
In the Chemistry lab, Clorice despondently receives her test result: C-. Failure to bring up her grade will cost her place on the swim team. Zeke offers to tutor her in return for swimming lessons.
In a small dinghy, the two float across the deserted pool. Zeke relates a childhood incident when, while swimming in a pond, he got his foot entangled in some underwater plants. Narrowly saved from drowning by his brother, Zeke henceforth lived in irrational dread of some underwater menace, waiting to reclaim him.
Touched by his confidence, Clorice slips into the water; leans on the dinghy, reassures Zeke against any such threat in a swimming pool, and coaxes him into putting his hand into the water.
Zeke notices a rancid smell - it reminds him of acid. In the water, something seizes his hand and wrenches him head first into the pool. With a gasp, he breaks free to the surface. Clorice pulls him onto the dinghy. Stunned with fear, he reports, in total seriousness, to have been grabbed. The dinghy is violently bumped from beneath. It bucks violently. Something seizes Clorice's wrist and drags her toward the water. Just in time, Zeke grabs her. With forced calm, Clorice suggests they stay put until someone comes.
With a lurch, the dinghy upends, tipping them into the pool. Treading water, Clorice gently takes hold of Zeke. Beside them, the end of a long pole slips into the water. Charlie yells at her to grab it.
Having been the lifeguard when the pool first opened, Charlie's girlfriend's little brother drowned. When Charlie tried to save him, a powerful, unseen grip pulled the boy away from him. The boy died. No one believed Charlie - until three more people drowned.
The pool was built, he explains, on the site of an old cemetery, whose bodies were moved. Charlie supposes they must have missed one - its spirit must want revenge for being disturbed. Zeke has an idea. He leads Clorice and Charlie to the Chemistry lab, and takes a bottle of Methyl Orange: it's time for an experiment!
By the pool, Zeke, in a pair of rubber gloves, pours in some Methyl Orange. If, as its smell suggests, the spectral fiend is made of acid, exposure to Methyl Orange should turn it red. Soon enough, the smell returns.
Deep in the pool, a region of water starts to darken and bubble. A man-sized mass of dark red starts to solidify. In the water, a crouching, lividly red figure launches a hand to grab Zeke's shirt. Charlie pulls Zeke back. Clorice screams.
Chest-deep in the pool, shrouded in drapes of rotted cloth, is a figure whose bare skull is matted with ancient wisps of hair. The entire profile, body and shroud, is bleached dark, pinkish red. The eyeless face stares at Charlie, who stands frozen with horror. While Clorice steers Charlie away, Zeke grabs an oar. As the red Corpse reaches for him, Zeke swings, but the oar, with a splash of water, passes seamlessly through it.
With Clorice and Charlie, Zeke hurries into the locker room. He realises the Corpse to be made of water. Charlie lies on a bench, in shock. Nearby, the grill of a floor drain starts to emit a dark red liquid. Zeke sniffs - and the Corpse is standing over them. Clorice screams, and they both run.
By the pool, they despair at having left Charlie defenceless - but how to stop the Corpse? Suddenly, Clorice has an idea. She takes the bottle of manganite - as previously combined by Zeke with water for the combustive effects of his volcano. Clorice tries to unscrew the cap, but Zeke knocks it out of her hands and into the pool - if it touches the moisture on her hands, this stuff will burn them - she needs gloves.
Clorice dives into the pool after the bottle. Meanwhile, on the tiles by Zeke, red water oozes towards the pool. Clorice surfaces with the bottle. Zeke yells at her to swim, as the Corpse is in the water. Sure enough, in skeletal form, it towers above the surface of the pool, and wades towards her. Zeke yells in desperation for her to move, but she's paralysed with fear.
With a strangled yell, Zeke leaps into the pool. The Corpse turns to regard its fresh prey. Clorice, woken from her trance, carries the bottle out of the pool. She pulls on Zeke’s rubber gloves.
Zeke desperately treads water, and backs to the edge of the pool. From behind, Charlie lifts him out. Clorice, now wearing rubber gloves, hurls some manganite into the pool.
The water around the Corpse, including that of which its spectral body consists, steams and froths. The Corpse writhes, and dissolves into white vapour.
The evil spirit, closes Stig, never bothered anyone again, and Charlie was no longer tortured by his memories. The Midnight Society huddle for a vote. Sam affirms the story to be great, but the vote has to be unanimous, and wasn't. Stig graciously thanks them for the shot. However, add Betty Anne and Gary, they've decided to invite him to a few more meetings, with an eventual second chance. If by then Kiki can abide his company, then he's in.
This episode provides examples of:
- Adults Are Useless: Subverted. Charlie is at first as helpless as anyone. Paralysed with shock on sight of the Corpse, he revives just in time to pull Zeke out of the pool to safety.
- Axe-Crazy: The Corpse, a forgotten resident of a relocated cemetery, is indiscriminately, murderously furious at intrusion into its resting place by swimmers.
- Big Damn Heroes: Zeke jumps into the pool to distract the Corpse from Clorice; Charlie lifts Zeke from the water and out of immediate danger, and Clorice gives the Corpse a lethal dose of manganite.
- Cassandra Truth: After Billy’s death, Charlie warned the school that the pool was not safe. No one believed him until three more people died.
- Chekhov's Gun: Zeke's manganite experiment from the beginning of the story ends up becoming instrumental in defeating the Corpse.
- Deadpan Snarker: Clorice sometimes wryly relieves Zeke's inordinate worries.
- Death of a Child: In the 1954 prologue, young Billy is dragged beneath the water and drowned.
- Deer in the Headlights: When Clorice jumps into the pool to retrieve the bottle of manganite, she freezes as the Corpse slowly advances towards her. She snaps out of it when Zeke junps in the pool to distract the Corpse.
- Defrosting Ice Queen: While Clorice is initially disdainful of Zeke's eccentricity, she appreciates his pool discovery, and sympathises with his hydrophobia.
- Dem Bones: The Corpse's face is that of a bare skull.
- Distant Prologue: The beginning takes place in 1954, where young Billy is attacked by the Corpse before it jumps to forty-two years later.
- Education Through Pyrotechnics: The present-day portion of the story starts with an explosion in a high school chemistry class. The heroes use supplies from the same lab to defeat the zombie.
- Elemental Embodiment: The Corpse's spectral body is composed of water.
- Endearingly Dorky: Greta is openly fond of Zeke's polite, naive enthusiasm. On his revelation of the secret pool; offer to tutor her in chemistry, and confidence of his hydrophobia, Clorice also warms to him.
- Evil Smells Bad: The Corpse is heralded by a smell akin to rotten eggs, which Zeke identifies as acid.
- The Friend Nobody Likes: Downplayed. In the least, Tucker genuinely likes Stig and was even the one to propose he join the Midnight Society in the first place. Gary seems wary of a new member who aggravates Kiki, and Betty Anne doesn't seem to have a problem with him. But as for everyone else, they're very hesitant to let him join, even though he gives them a good story.
- Give Geeks a Chance: On getting to know the somewhat awkward Zeke, Clorice warms to him.
- I Let Gwen Stacy Die: A possible subversion; while Charlie is grief-stricken and traumatised by his inability to save Billy, he doesn't openly blame himself.
- Impending Doom P.O.V.: Unsuspecting prospective victims are often shown from the Corpse's submerged perspective.
- Knight of Cerebus: While this show has a prolific share of macabre, often murderous fiends, the Corpse causes the most in-story wanton death.
- My Greatest Second Chance: By helping Zeke and Clorice defeat the Corpse, Charlie is able to avenge Billy and put his guilt to rest.
- No Name Given: While Clorice addresses it as "Red", the credits refer to the invisible zombie as the "Corpse".
- Nothing Is Scarier: Subverted. While the presence of the Corpse in the pool when it was invisible was very suspenseful, the sight of it when it becomes visible is just as terrifying.
- Opposites Attract: Zeke is a science genius with a lot of fear to overcome. Clorice is a fearless athlete.
- Pre-Mortem One-Liner: Clorice delivers one to the Corpse before dissolving it with manganite:Clorice: Yo, Red! Catch!
- "Psycho" Strings: A shrill, pointed motif creates a very effective sense of dread when the Corpse is on the scene.
- Sadist: The Corpse has an apparent fondness for slowly stalking towards its victims, letting them take in the horror of their impending doom.
- Science Hero: Zeke's chemical knowledge provides the means to reveal the murderous spectral Corpse. Clorice later weaponises against the Corpse Zeke's demonstration of the combustive properties of manganite.
- Shout-Out: Habitation of a swimming pool by a murderous spectral corpse somewhat recalls a scene in the climax of Poltergeist.
- Silent Antagonist: The Corpse never utters a word as it attacks people. It’s unknown if it can even speak.
- Sinister Silhouettes: Across the decades-closed swimming pool, a bit of the covering sheet briefly rises in a human-shaped bulge...
- Thousand-Yard Stare: On realising the Corpse to be back, Charlie speaks with a distant stare of awed, despairing dread.
- Tough Room: Despite the story being good, even universally agreed on by many fans as the scariest episode in the series, the Midnight Society don't think it's good enough to let Stig join.
- Would Hurt a Child: In its blind, insatiable rage, the Corpse wants to drown anyone and everyone who trespasses on its resting place - including young Billy.
