Literature: Harry Potter and the Chamber of Secrets
"It is our choices, Harry, that show what we truly are, far more than our abilities."Harry Potter and the Chamber of Secrets
— Albus Dumbledore
is the second book in the Harry Potter
series. Published July 2, 1998.
The main plot involves the Chamber of Secrets, a hidden chamber within Hogwarts built by Salazar Slytherin. A big fan of Fantastic Racism
, Slytherin built the Chamber to house a monster which can only be controlled by his heir and which is intended to attack all those Muggle-borns
"unworthy to study magic". Now, someone has opened the Chamber, implying the Heir of Slytherin has returned to Hogwarts, but who is it?
You may have noticed this storyline has rather little to do with the overall Story Arc
is often accused of essentially being devoted to a Wacky Wayside Tribe
for this reason. In reality, the book is just an Innocuously Important Episode
, and introduces a major Chekhov's Gun
among other bits of Foreshadowing
for several later books, particularly Harry Potter and the Half-Blood Prince
. Indeed, still being a freshly-starting-out-author, Rowling was told to leave out some parts she wanted to leave in
and later had to cram them into book six.
Followed by Harry's third year at Hogwarts, in Harry Potter and the Prisoner of Azkaban
Tropes exclusive to this book or at least especially prominent in it:
- Actually Pretty Funny: Malfoy mocks Harry's fanboy Colin Creevey. Harry, who's by that time very tired of Colin's constant squealing, finds the imitation both cruel and rather accurate.
- He also actually enjoys Fred and George's mockery about the whole "hair of Slytherin" business because it assures him that they aren't actually taking it seriously.
- Absurdly Spacious Sewer: What kind of building has pipes big enough for a huge snake to move around in?
- The Alleged Expert: Gilderoy Lockhart was hired as the new Defense Against the Dark Arts instructor due to his track record of defeating magical monsters. His only real skill turns out to be stealing the credit from the wizards who really defeated those monsters.
- Alternate Identity Amnesia: Happens to Ginny when Tom Riddle takes over.
- Are You Sure You Can Drive This Thing?: "No, but we're far too anxious to consider another plan."
- Backwards Firing Wand: Ron's wand is damaged and becomes prone to firing spells through the wrong end, the one pointing towards the spellcaster... which is good news when Professor Lockhart steals it and tries to use it to erase Ron's and Harry's memories...
- Bathroom Stall of Overheard Insults
- Bat Scare: Non-flying example: Huge crawling masses of spiders flee from Hogwarts. They do no harm, but badly frighten Ron, an arachnophobe.
- Becoming the Boast: Subverted. Lockhart seems like a Know-Nothing Know-It-All with a grossly inflated ego. In reality...he's exactly that, plus amoral enough to steal other people's accomplishments and leave a child to die. When the staff suggest he go after the Basilisk, it's clear they're doing it to watch him squirm. When Harry and Ron *force* him to accompany them, since he's the closest thing they've got, he betrays them at the first opportunity.
- Big Bad: Lucius Malfoy or the memory of Tom Riddle.
- Bigger Bad: Voldemort does not personally appear in this book, but the conflict at Hogwarts this year is caused by his diary containing a fragment of his soul.
- Blank Book: Riddle's diary. At first.
- Blasting It out of Their Hands: The Expelliarmus spell, which Harry learns in this book.
- Break the Haughty: Lucius avoids prison time but suffers several blows to his ego. A twelve-year-old both stops his plan and tricks him into freeing Dobby, who takes the first opportunity to pay Lucius back for years of abuse by effortlessly blasting him down a flight of stairs. And Lucius also lost his job as one of the governors of Hogwarts, something he could have avoided if he hadn't threatened the other governors' families.
- Camera Fiend: Colin Creevey.
- Caught with Your Pants Down: Percy. Now that you're not 12, give this passage a close read.◊ Averted, in that we find out what he was actually doing — making out with his girlfriend, who he hadn't told anyone about.
- Chekhov's Gun: The whole series gets its own page.
- Chekhov's Gunman: Harry, Ron and Hermione interact with Myrtle throughout the book, and only near the end realize that she's the girl the Heir of Slytherin killed fifty years ago.
- Clown Car: Arthur Weasley's Ford Anglia is enchanted to be Bigger on the Inside.
- Comically Inept Healing: Lockheart attempts to heal Harry's broken arm with a spell but accidentally removes all of the bones in his arm instead.
- Cool and Unusual Punishment: Harry having to answer Lockhart's fan mail as the punitive detention he incurred for flying the car to school. (He doesn't see it as such, though.)
- Contrived Coincidence: All the victims of the basilisk happen to see it indirectly, even taking into account those who are looking out for it.
- Cover Identity Anomaly: Harry and Ron use Polyjuice Potion to pretend to be Crabbe and Goyle, but their infiltration of Slytherin House is stymied by the fact that they don't know how to get in to Slytherin's chambers. They ask a passing student, but she's from Ravenclaw. Fortunately, Crabbe and Goyle are so dim that they're not really acting out of character.
- Critical Research Failure: In-universe — Tom Riddle seems to think that werewolves are much more animalistic than they actually are, considering that his false accusations towards Hagrid involved raising "werewolf cubs."
- The Dandy: Gilderoy Lockhart
- Dangerous Device Disposal Debacle: Ginny attempts to stop the attacks on the school by flushing Tom Riddle's diary down the toilet. Unfortunately, the toilet backs up and Harry and Ron find it, bringing it back to the Gryffindor common room and right back into Ginny's hands.
- Darker and Edgier: While not as tense and brooding as the final books, Chamber of Secrets presents a huge leap in violence from the first book. More importantly, though, it introduces elements that are flat-out horror and can be argued not to have been surpassed even in the final books. Harry hearing the Basilisk's macabre ramblings while the monster stalks the piping system and the sinister, hostile message in blood aren't even the only examples.
- Dead Guy Junior: Tom Marvolo Riddle, named for his father and his maternal grandfather. Or for both grandfathers, considering that "Tom" is usually short for "Thomas."
- Diary: Tom Riddle's.
- Didn't Think This Through: Harry and Ron when they steal Mr. Weasley's Flying Car. Granted, they're twelve years old at the time. Lampshaded by McGonagall when she points out other, more reasonable, things they could have done to get to Hogwarts, and Harry reluctantly admits to himself that stealing a car was pretty stupid.
- Also, over the month they spent brewing the Polyjuice Potion to sneak into the Slytherin dorms, not one of the trio realized they have no idea where those dorms are.
- Dinner with the Boss: Mr. Dursley's potential client and his wife come over to discuss a promotion over dinner. When Harry retires to his bedroom, Dobby the house elf appears and begs Harry not to return to Hogwarts. When he refuses, the house elf levitates Aunt Petunia's pudding and drops it.
- Disappointed In You: Dumbledore and McGonagall to Harry after he flies the car to Hogwarts.
- Disney Death: Ginny Weasley gets one in the Chamber of Secrets.
- Does This Remind You of Anything?: Harry's (and Ginny's) interaction with Tom Riddle's Diary is extremely similar to that of an online chat room, as well as the part about the person being conversed with being revealed to not be trustworthy at all to begin with, a similarity made even more apparent in the film. It looks like the fear of every early internet user's parents: an unsuspecting kid is taken advantage of by someone they met online. Naïve Ginny pours out her soul “to an invisible stranger” she knows only through their text conversations and thinks she is making friends with this person. In reality he’s manipulating her, getting her to do things she normally wouldn’t, and when she goes to meet him in person she nearly ends up dead.
- Harry has to save a girl by going into a chamber of secrets and fighting a giant snake that belongs to a very weird, much older guy that's been corrupting her for the whole book. With a legendary sword that holds strange powers. Uh-huh.
- Do Wrong, Right: Arthur Weasley is far more pleased than his wife when his sons steal his flying car and use it to pick up Harry.
- Eating Optional: When Harry visits Nearly Headless Nick's Deathday party, there's a banquet of rotten food laid out for the ghosts. Hermione figures they let the food rot so that the flavors are strong enough for the ghosts to actually taste.
- Enemy Within / The Killer In Me: Poor Ginny.
- Eureka Moment
- Harry deduces that Lucius Malfoy was the one who set the whole plot in motion when he saw Malfoy arrive with Dobby, the elf that warned Harry in the first place.
- Hermione has one when she realises what the monster of Slytherin is, but doesn't get to tell anyone else. Harry gets the moment secondhand when he reads her note later.
- Everybody Lives: Assuming the Basilisk and the soul fragment of Tom Riddle don't count, this book and The Prisoner of Azkaban are the only books in the series where no character dies during the course of the story (though Moaning Myrtle's death is a major part of the backstory).
- Eye Scream
- Fawkes vs. the Basilisk, to give Harry a fighting chance against the latter.
- Also a book the Ministry had confiscated, mentioned in Ron's response to Harry asking him how a book could possibly be dangerous: it burned out its reader's eyes.
- Face Palm: Flitwick does one with both hands after Lockhart suggests students visit him for advice on Entrancing Enchantments.
- Feet of Clay: Gilderoy Lockhart
- Follow The Spiders
- Foreboding Fleeing Flock: Harry and Ron find a swarm of spiders leaving Hogwarts by an open window and heading for the forest. They later find out that the castle is home to a monster that spiders consider their mortal enemy: the basilisk.
- "Potter, you've got yourself a girlfriend!" More seriously, when Ginny decides to confess, who does she go to? One of her older brothers? One of the teachers? No. She goes to Harry.
- In chapter 14, when second-years sign up for electives to take next year, it mentions Hermione signed up for every class offered. This becomes a key plot point in the next book.
- "I would advise you not to shout at the Azkaban guards like that. They won't like it at all."
- "Sir, why don't you apply for the Headmaster's job?" Malfoy to Snape.
- The fact that the first half of the book is spent with the Trio trying to figure out whether or not Malfoy's up to something. Four years later, it's Harry by himself, because no-one believes him. He was right this time.
- "Maybe [Tom Riddle] murdered Myrtle; that would've done everyone a favor..." He did.
- The first time Harry sees Tom Riddle's name, he has the strange feeling he knows Tom. He should: he's had a chunk of the guy's soul stuck to him since he was a year old.
- A more subtle one, but Lockhart suggests that, on Valentine's Day, they ask Snape to teach them how to make a love potion, whereupon the narration remarks that Snape had an expression that clearly said that anyone who turned up asking for a love potion would be force-fed poison. In Book 6, Ron inadvertently consumes both a potent love potion and a lethal poison in rapid succession, though admittedly not from Snape.
- Getting Crap Past the Radar: The reference to the Japanese golfer joke. The only Japanese golfer joke has the punchline, “What do you mean, wrong hole?
- Giant Spider: Aragog and his relatives.
- Hammy Herald: Fred and George show their support for Harry not by squashing rumors about him, but rather by following him around crying "Make way for the heir of Slytherin! Seriously evil wizard coming through!"
- Hearing Voices: Harry is the only person who hears a voice in the wall that repeats "kill!" He, Hermione, and Ron realize this is not a good thing to hear voices only he can hear. It turns out to be the basilisk moving in the pipes.
- Heartwarming Moments: Subverted in-universe. What McGonagall thinks is is a CMOH is just the first lie Harry could come up with so he and Ron wouldn't get in trouble. Ends up being relevant to the plot because actually following through on the lie leads them to figuring out the mystery.
- Heel-Face Turn: Dobby at the end, going against his master.
- Hijacked By Voldemort: The book plays out like this. So a monster controlled by the Heir of Slytherin has been attacking students. At the end, we discover that -surprise!- Voldemort was behind the entire thing.
- Hoist by His Own Petard: Ron, when trying to curse Malfoy ("Eat slugs!"), inadvertently curses himself, thanks to his broken wand. This is important later with Lockhart, hit by his own rebounding Memory Charm while using Ron's busted wand.
- Holding It for a Friend: Filch claims that the Kwikspell letter on his desk is for a friend so that Harry doesn't guess that he has no magic.
- Hot for Teacher: Hermione seems to one of many girls who have a crush on Lockhart.
- I Have Just One Thing to Say: After the climax Dumbledore gives a criticizing speech to Harry and Ron about their behavior, only to finish with: "Therefore, it is only fitting that you both receive ... beat ... Special Awards for Services to the School."
- I Just Want To Be Free: Dobby.
- I Never Got Any Letters: In the first chapter, Harry is upset that his friends haven't written to him all summer. Then it's revealed that an elf has been intercepting their letters.
- I Never Said It Was Poison: Dobby inadvertantly reveals that he has been stopping Harry's letters when he mentions that Harry's friends haven't written to him — which is something he shouldn't be aware of.
- Informed Ability: In-universe: Lockhart completely fails to live up to any of his hype, as Harry and Ron are quick to point out.
- Inept Mage: Gilderoy Lockhart.
- Innocuously Important Episode: Some readers found the novel to be heavy in the Padding department, particularly the Wacky Wayside Tribe aspect. But the novel is quietly setting up Harry Potter and the Half-Blood Prince and, to some extent, foreshadowing Harry Potter and the Deathly Hallows. To list:
- Harry winds up on Knockturn Alley, at Borgin and Burkes' dark antique shop. There he hides in a dark cabinet and sees Lucius Malfoy sell Borgin an opal necklace that kills people. In the sixth book, Harry tracks Draco Malfoy to see him arrange the repairs of the Vanishing Cabinet, implied to be the same one he hid in. Also, the opal necklace almost killed Katie Bell, courtesy of Malfoy.
- Ginny starts her crush on Harry. They finally get together in his sixth year.
- The trio spend the year suspecting Malfoy of scheming. In the sixth year, Harry suspects him again and he's right.
- Harry and Hermione, having dealt with a dark magical diary from the past, are wary of the Half-Blood prince's textbook. They are right to be, although it's not the book itself, but a spell written in it.
- Harry and Ron deduce from the decorations in the trophy room that Tom Riddle was a Head Boy when the Chamber was opened and must have known about it. They search for the Half-Blood Prince there, but find nothing. It turns out to be Snape.
- Moaning Myrtle's bathroom is crucial to the events of the book. Four years later, it is again.
- Harry learns the disarming charm at the duel club and is about to use it on Draco. Four years later, he finally casts the spell on him, which has important consequences.
- Dobby is introduced, shown to be capable of potent magic such as apparition without the limitations that human wizards have, and freed. All of that is a crucial element in the final book.
- Draco mentions that the Malfoys have "their own Chamber of Secrets" in their home, but the Ministry agents do not find it. In the seventh book, this is where the Golden Trio are imprisoned.
- Lucius Malfoy uses a dark artifact to his own ends in an intricate plot. The destruction of said artifact backfires on him and his master in the sixth and seventh book, where it turns out to be a Soul Jar belonging to Voldemort.
- After Dumbledore's expulsion, Malfoy suggests to him that he applies for Headmaster. This is where Snape winds up in the seventh book.
- The basilisk's venom that destroyed the diary and Gryffindor's sword come in handy for the destruction of the other Horcruxes as well. Also, Ron and Hermione reopen the Chamber of Secrets specifically to obtain the basilisk's fangs and destroy the remaining Horcruxes.
- Draco Malfoy calles Hermione "filthy little Mudblood" and it is stressed upon how highly offensive the term is to Muggleborns. Five books later we find out that in the past Snape called Harry's mother that, which was the catalyst for half the events in the series.
- Dumbledore points out that only a true Gryffindor can pull Godric Gryffindor's sword out of the Sorting Hat. Neville Longbottom, The Unchosen One, does so when he finally proves that he's not a coward and destroys Voldemort's last Horcrux. Also, the sword again kills a snake.
- Dumbledore tells Harry that he suspects a part of Voldemort may live inside him. This proves true and Harry turns out to be an unintentional Horcrux.
- Involuntary Group Split: Gilderoy Lockhart's wayward spell sets off an earthquake that separates Ron from Harry, so Harry has to go alone into the Chamber.
- In retrospect, Ron trying to comfort Ginny after the attack on Mrs. Norris by telling her that "they'll catch the maniac who did it and have him out of here in no time." Assuming Ginny had begun to suspect herself at that point, this might also count as Oblivious Guilt Slinging. After all, at the end of the book, she was convinced that she was going to be expelled. Way to go, Ron.
- When wondering what Tom Riddle got a Special Award for Service to the School for, Ron sarcastically suggests that maybe he killed Myrtle as "that would've done everyone a favor." Riddle did kill her and he got the award for successfully framing Hagrid as her murderer.
- Another potential example: Hermione suggests that whoever flushed Riddle's diary may have been the culprit, trying to stop anyone from finding out details about the last time the Chamber was opened. It was the culprit (sort of), but they did it to stop the attacks.
- Harry wonders if, due to his speaking Parseltongue, he's a distant relative of Salazar Slytherins. It turns out that, through the Peverells, he is related to Voldemort, so he actually is, in some fashion, related to Slytherin.
- I Thought Everyone Could Do That: Harry's Parseltongue.
- Living Memory: The Diary of Tom Riddle.
- Loophole Abuse: There's a law to stop wizards from misusing muggle artifacts, but Mr Weasley uses a loophole in a law that he wrote to let him misuse them on his own time.
- Love Potion: Lockhart suggests students visit Snape for advice on brewing one. Snape's expression makes it clear anyone who does so risks being poisoned.
- Magic Misfire: Everything cast with Ron's broken wand. This becomes important.
- Mailer Daemon: Tom Riddle
- Malicious Slander: A good portion of the school believes that Harry is the Heir of Slytherin after the incident with the snake at the Dueling Club.
- Milky White Eyes: Aragog
- Mind Rape: What Riddle's Diary did to Ginny.
- Lockhart's only real skill, aside from looking good.
- Missed the Bus: Dobby blocks Harry's access to Platform 9¾, causing him and Ron to miss the Hogwarts Express and take alternative transport. Hilarity Ensues.
- Monster of the Week: Subverted; the Heir of Slytherin turns out to be Voldemort.
- Motive Misidentification: While Tom certainly didn't mind using the Basilisk on Muggle-borns, he was less interested in "purging the school" and more in trying to bait Harry.
- Muggle Born of Mages: This book introduces the concept of Squibs, revealing Filch to be one.
- Narm: In-universe.
- Invoked with the twins' valentine to Harry. Fred and George continually tease him with it and Peeves adds a dance routine.
- Dudley's ass-kissing compliment to the Masons ("We had to write about our hero at school, Mr. Mason- I wrote about you"). Harry hides under the table to conceal his laughter from the Dursleys.
- Nice Job Fixing It, Villain: Lucius Malfoy planting the diary on Ginny Weasley. As we learn in the sixth book, this set off a chain of events that destroys one of Voldemort's Horcruxes and provides Dumbledore with the first real proof that Voldemort split his soul. Good going, Lucius.
- Non-Malicious Monster: The basilisk might have been able to kill you only by looking at you. But it was controlled by "the heir of Slytherin" and didn't do anything unless he asked it to kill someone. Then again, the things it said in snake language that Harry overheard sounded pretty horrible.
- Noodle Incident: During the final confrontation in the Chamber, Diary!Riddle says that Dumbledore never seemed to like him as much as the other professors. Exactly what young Riddle did to trigger Dumbledore's suspicions won't be revealed until the sixth book.
- Not Me This Time: Harry and Ron use Polyjuice Potion to imitate Crabbe and Goyle, Draco Malfoy's two Mooks, in the hopes of getting Draco to admit that he's the heir of Slytherin, and thus the cause of all the shenanigans happening at Hogwarts that year. Instead, they hear Draco ranting about how thrilled he is that it's happening and how he'd love to congratulate whoever is actually behind it.
- Orifice Evacuation: Slug-puking spell.
- Parody Magic Spell: Harry threatens Dudley with the words "Jiggery pokery! Hocus pocus! Squiggly wiggly!", and earns himself an afternoon of menial housework for his joke.
- Pensieve Flashback: Although the actual Pensieve wasn't introduced until Harry Potter and the Goblet of Fire, Riddle's diary displays this here, two books earlier.
- Politically Incorrect Villain: It's in this book that Malfoy introduces the anti-Muggle-born slur "Mudblood".
- Portal Slam: Harry and Ron rebound painfully from the portal to Platform 9¾.
- Post Mortem Comeback: The entire basis of the plot; Voldemort hid pieces of his memories in a book, who took the form of Tom Riddle, but it's inverted — Voldemort himself was already alive to begin with... somewhat.
- Predecessor Villain: Salazar Slytherin was the guy who built the Chamber of Secrets and put the Basilisk there in the first place, but he's been dead for nearly a thousand years when the story begins.
- Punny Name: Knockturn Alley, like its good counterpart Diagon Alley, is this ("Nocturnally" or "Nocturne" Alley).
- Ransacked Room: Ginny ransacks Harry's dormitory in order to get Tom Riddle's diary back.
- "The Reason You Suck" Speech: Harry gives one to the memory of Riddle, gloating over how his Muggle-born mother reduced Voldemort to almost nothing.
- Red Herring: Percy, Hagrid and Malfoy — and Harry — are all set up as possible Heirs of Slytherin, with Malfoy being the choice that's so obvious it's stupid, and Percy and Hagrid both having Really Big Secrets that make them act suspicious. Naturally, Malfoy is the one our heroes suspect and they spend half the book finding out that it isn't him.
- Reptiles Are Abhorrent: Basilisk. Also the decoration of the Chamber of Secrets. Salazar must have been swapping design tips with Jafar.
- Right Behind Me: Harry and Ron excitedly speculate on reasons why Snape is absent at the beginning of the year, not realizing that Snape is actually just behind them.
- Right for the Wrong Reasons: Ron's sarcastic suggestion that Tom Riddle might have killed Moaning Myrtle.
- Ron also suggests that Dobby might belong to the Malfoys, and that his whole spiel about "protecting" Harry is just Draco's trick to get him sent home. Dobby does belong to the Malfoys, but his motive is legitimately good.
- Saved by the Awesome
- Sealed Evil in a Can:
- The titular chamber contains Slytherin's monster, an enormous basilisk.
- Also, Tom Riddle's diary has the "memory" of the teenage Voldemort sealed inside, which Ginny unknowingly awakens through her liberal use of the diary.
- Serpent of Immortality: The basilisk that lives beneath the school has an incredibly long lifespan. It was first stored under the school around a thousand years earlier.
- Shrine to Self: Lockhart's room is filled with pictures of himself. Since this is the wizarding world, they're all nearly as vain as he is and tend to nod along to whatever he's saying.
- Shrinking Violet: Ginny, pretty much only in this book as she's hardly in the next two and in the fifth she's revealed to have Taken a Level in Badass.
- Significant Anagram: Tom Marvolo Riddle <-> I am Lord Voldemort. Other languages revise the anagram to make sense in their tongues — or change his birth-name.
- One of the funniest examples of this is the French version, which gives him the name “Tom Elvis Jedusor.”
- Small Name, Big Ego: Gilderoy Lockhart
- Soul Jar: Tom Riddle's diary.
- Spider Swarm: The giant spiders (also known as Acromantulas) appear to be social, although instead of a queen, they are led by an elderly male spider named Aragog. It's explicitly stated that Aragog had a bride, so apparently, Acromantulas females don't feed on their male.
- Spinning out of Here: Travel by Floo sends the traveler spinning to his/her destination.
- Stalker with a Crush: Colin Creevy is this to Harry in this book.
- Stealing The Credit: Lockhart, on a fairly horrifying scale. Be careful if you're a witch or wizard who has done something either brave or impressive. He doesn't just steal the credit, he wipes your memories.
- Stop Helping Me!: In-universe, Dobby. Harry actually asks him to never try and save his life again at the end. Good thing Dobby didn't listen.
- Stronger with Age: The Basilisk.
- Sword Cane: Lucius Malfoy has one which he attempts to use against Harry Potter. However, Dobby has something against it.
- Tempting Fate: Inverted. Ron says of Hermione's plan for the Power Trio to impersonate Slytherins, "Have you ever heard of a plan where so many things could go wrong?".
- This Is Gonna Suck: Harry and Ron fully expect to be expelled after being busted by Snape for flying the car to Hogwarts.
- Ron when he receives the Howler.
- Thoroughly Mistaken Identity: Professor Binns is always calling students by the names of students of long ago.
- Tom the Dark Lord: Trope Namer.
- Villain of the Week: Subverted. Up until the last couple of chapters it looks like the series will be heading this way, with the Big Bad Voldemort introduced in the first book and the mysterious Heir of Slytherin being the main villain in the second book. Near the end however it's revealed that not only is Voldemort the Heir of Slytherin, but a memory of his younger self has been driving the plot the entire time. Starting with the third book, all of the main antagonists (except Umbridge) are explicitly linked to Voldemort.
- Villain with Good Publicity
- Lucius Malfoy, who is a distinguished Ministry official despite being a former Death Eater. He manages this by attributing his past affiliation with the Big Bad to the Imperius Curse.
- Lockhart is another example, although he's more of an Anti-Villain.
- Watch Out for That Tree!: What tree?! The Whomping Willow!
- Weaksauce Weakness: The Basilisk would die at the crowing of a rooster (presumably because it is hatched from a chicken's egg incubated by a toad). One wonders just how effective a weapon a Basilisk would be to a dark wizard in any other situation, given everyone knows this and roosters aren't exactly hard to come by.
- Well-Intentioned Extremist: Dobby.
"Your Bludger?" said Harry, anger rising once more. "What d'you mean, your Bludger? You made that Bludger try and kill me?"
"Not kill you, sir, never kill you!" said Dobby, shocked. "Dobby wants to save Harry Potter's life! Better sent home, grievously injured, than remain here, sir! Dobby only wanted Harry Potter hurt enough to be sent home!"
- What Measure Is a Non-Human?: Those poor mandrakes. Even though everything suggests that they are sapient, social lifeforms (they get "moody and secretive" in their adolescent phase, enjoy partying, and when they reach adulthood, start moving into each other's pots), nobody seems to think chopping a mandrake up for a potion is any different than chopping up a carrot.
- Who Would Be Stupid Enough / Description Cut / Gilligan Cut: At the very end of Chapter 9, "The Writing on the Wall", Hermione comes up with the idea of using Polyjuice Potion to get information from Malfoy. However, the book with info on how to make it is in the Restricted Section of the library, and they need permission from a professor to take out the book, which would raise suspicion from any professor they ask.
"Oh, come on, no teacher's gonna fall for that!" said Ron, "they'd have to be really thick..." [end chapter]
[start of next chapter] Since the disastrous episode with the pixies, Professor Lockhart had not brought live creatures to class...
- Why Did It Have to Be Spiders: Poor, poor Ron. However, it speaks to his character that he goes into the forest anyway.
- Wondrous Ladies Room: Hermione tries to give Moaning Myrtle this excuse for bringing Harry and Ron into the girls' bathroom Myrtle haunts. As the bathroom is filthy and largely abandoned, Myrtle doesn't really buy it.
- Won't Take "Yes" for an Answer: After the attack on Nick and Justin, Hagrid bursts into Dumbledore's office to explain that he was talking to Harry only seconds beforehand and he'll swear that Harry's innocent in front of the Ministry if necessary. Dumbledore repeatedly tries to interrupt before half-shouting that he completely agrees with Hagrid.
- Wrote the Book: Inverted; even though Lockhart literally wrote the book on dealing with magical pests, that doesn't mean he has a clue about it.
- Xanatos Gambit: Lucius Malfoy's plan has two possible outcomes: either Ginny is caught, thus disgracing Arthur Weasley and his Muggle Protection Act, or the culprit is not apprehended, and either kills every Muggle-born in the school or drives them all away. The former seems to be his preferred option, interestingly enough, but either would presumably satisfy him. Of course, his plan backfired worse than he could have possibly imagined, which we learn in Deathly Hallows.
- You Are Better Than You Think You Are: Harry feels unworthy of his fame as well as his house, Gryffindor. Dumbledore manages to assure him that he does belong in Gryffindor, showing Harry the sword as proof.