What An Idiot / Harry Potter and the Chamber of Secrets

• Dobby the house elf hears from his masters, the Malfoys, that they're going to unleash a great evil at Hogwarts that will endanger Harry Potter. The elf, contrary to most of his kind, is not blindly loyal; he decides he has to save the boy. The only problem is he's bound to not give away his master's secrets, or what the plot entails.
  You'd Expect: Given that the plot will be taking place at Hogwarts, that Dobby would go to Dumbledore, the headmaster, and start dropping hints as he did with Harry. From what we see of Lucius Malfoy, he didn't seem to bother telling Dobby to not warn anyone, and given that Dobby can apparently still nod or shake his head to any question, it should be ridiculously easy for him to leak out the info. Even if not, Dumbledore in book five reveals that he can perform Legilimency on an unwilling house elf and thus can temporarily break the Geas.
  Instead: Dobby goes straight to Harry Potter's bedroom, confiscating his letters from Ron and Hermione, and gets him in trouble when Harry refuses to stay home from Hogwarts. The elf then continues to do this, without explaining to Harry or giving more than a few hints about the danger.
  As A Result: Harry gets irked at Dobby, especially since the attempt with the rogue Bludger could have killed him, and refuses to heed the order.
• Dobby tells Harry that he can't go back to Hogwarts. When Harry refuses, Dobby levitates Aunt Petunia's party pudding into the air and threatens to destroy it if Harry still insists on going. If the pudding is destroyed, Harry is going to be in huge trouble.
  You'd Expect: Harry to lie for the time being and say, "Okay, fine, I won't go back to Hogwarts."
  Instead: Harry refuses to say he's not going back to Hogwarts. Dobby destroys the pudding and skedaddles, the Dursleys are furious, and Harry gets locked in his room with the intention of never letting him go back to Hogwarts. If not for the Weasley brothers' escape plan, Harry would have been in there for the rest of the summer.
• Harry and Ron, thanks to Dobby, cannot pass through the magical barrier leading to the Platform 9 3/4, but all the other Weasleys are already there, the train has already left, and the boys are afraid (or at least implied to be) that Ron's parents might leave the station another way upon realizing that the barrier has been closed. Harry suggests that they return to the car they arrived by, because people are starting to stare at them.
  You'd Think: That the boys would just go to the car and wait for Mr. and Mrs. Weasley to get back, since they obviously wouldn't abandon their car, their only way back home. It's also improbable that Mr. and Mrs. Weasley would miss the fact that Harry and one of their sons have not boarded the train, so it is reasonable to expect that they would find their way back to the station to make sure the boys are okay. Failing that, as Professor McGonagall suggested, they could have just sent Hedwig, who they have with them, to Hogwarts with a message explaining the incident (this option might not have worked, as Dobby had already shown a willingness and ability to intercept Harry's mail, but it was still worth a try).
  You'd Also Think: Ron's parents would immediately notice that the last two members of the group, Harry and Ron, have not followed them into the platform. Molly should be especially aware, considering all the motherly care she puts on Harry despite (or because) of him not being her son nor experienced with the magical world. Instead, assuming the barrier was not blocked both sides for them too, it seems they didn't realize.
  Instead: Ron gets a "brilliant" idea to steal the car and fly it to Hogwarts.
  End result: The car's stealth mode malfunctions, it gets seen by non-wizards, Harry and Ron get detention, Arthur is fixed with a huge fine for this breach of the Statute of Secrecy, and the Weasleys lose the car. At least this one gets Lampshaded by Professor McGonagall.
• Voldemort gives a Horcrux, his old school diary, to Lucius Malfoy, as part of his plan to reopen the Chamber of Secrets, but since he's incapable of trusting anyone, he doesn't tell Lucius what it is, just that it's a powerful magical artifact.
  You'd Think: Voldemort would tell Lucius that he values the diary's safety more than he does Lucius', and that if Lucius does anything without Voldemort's express orders, death itself will not be enough to save the Malfoy family from very slow, very painful retribution. Hell, Voldemort could suggest that the diary has powerful wards on it that will be activated if Lucius uses it without permission, so that Lucius would hesitate to use it in a cavalier fashion even if he was 100% convinced Voldemort was dead.
  Instead: Voldemort does none of this, apparently confident that Lucius would never take any initiative whatsoever regarding Voldemort's stuff.
  As A Result: Lucius decides to carry out the plan anyway for his own ends, and gets a portion of his master's soul destroyed. Voldemort is less than amused when he finds out, and ultimately gets payback by forcing Draco to do an impossible task in the sixth book that he knows Draco will fail at.
• Throughout the year, muggleborn students, along with Filch's cat, suffer attacks from an unknown assailant that leave them petrified. Right after the first attack, it is established that a potion known as Mandrake Draught can cure the victims.
  You'd Expect: The school to try and buy some of this Draught from an outside source as soon as possible, so that the students can be treated quickly. Granted, the person responsible for the attacks might have destroyed or contaminated all the Mandrake Draught in the country earlier to prevent the school doing this, but we see no evidence to suggest this happened, and in any case, the idea of one person being capable of this, especially without nobody in the country realizing, seems a bit far-fetched. As a bonus, treating a victim immediately will allow them to identify their mysterious attacker.
  Instead: The school decides to make the Draught itself, even going so far as to grow its own Mandrakes. (The things are already planted, but still.) The problem is that the Mandrakes take most of the school year to mature, and therefore become usable.
  As A Result: The monster continues attacking people, and it's only through dumb luck that no one dies. Also, the assailant's victims miss out on a substantial part of their education for that year.
• In the Quidditch match between Gryffindor and Slytherin, Harry gets attacked by a rogue Bludger (actually another Dobby creation) that targets him and only him. Fred and George Weasley, the Gryffindor Beaters, have to constantly safeguard Harry from the thing due to his role as a Seeker, rather than looking after the team as a whole, and Harry can't focus on catching the Snitch because he's too busy trying to avoid a concussion or worse. As a result, Slytherin are able to get an easy 60-0 lead on Gryffindor. This goes both ways:
  You'd Expect: That Gryffindor, never mind Madam Hooch or any other member of Hogwarts staff, would call a halt to the match. Bludgers are supposed to attack as many people as possible regardless of team affiliation, so seeing one of them fixate on a player should have been grounds for an investigation, both in terms of Harry's safety and in terms of fairness.
  And In Fairness: The Weasleys do signal for time out to inform Wood and the rest of the team of what's going on. The idea of Slytherin possibly tampering with the Bludger is floated, and Alicia Spinnet demands that Wood forfeit the match to ask for an enquiry - although this would apparently mean conceding the match to Slytherin.
  But: Nobody in the crowd seems to bat an eye to what is going on (in the book at least; Hagrid, Hermione and Ron notice something's wrong but, as spectators, can't do anything). None of the staff, not even Madam Hooch, the referee of the game, call a halt to proceedings - Hooch just blithely asks if the Gryffindors are ready to resume play. And Harry himself, not wanting to forfeit the match, insists the Gryffindors keep playing as normal so he can deal with the rogue Bludger and have a better chance at catching the Snitch. This the Gryffindor team does, albeit with considerable reluctance.
  As A Result: Harry gets his arm broken by the rogue Bludger, and then has all the bones in said arm vanished by Lockhart. He ends up in the hospital wing waiting for his arm to grow back - a painful process.
  You'd Then Expect: Malfoy would take advantage of Harry being distracted to look for the Snitch himself and win the game for Slytherin.
  Instead: Malfoy stops to taunt Harry over his predicament, and is so caught up in it that he fails to notice the Snitch hovering mere inches above his left ear! Harry, however, does not fail to notice. And although he does get his arm broken by the Bludger, he still manages to catch the Snitch and win the game for Gryffindor. According to Fred Weasley, Flint would later give Malfoy a severe dressing down for this prime piece of idiocy.
• The game is over, but Harry has had his arm broken by the rogue bludger.
  You'd Expect: Gilderoy Lockhart would allow Harry to be taken to the Hospital Wing, where Madam Pomfrey could easily repair his arm in seconds. After all, it's her job and she is an expert healer, while Lockhart is a fraud who can barely do any magic other than Memory Charms.
  Instead: Lockhart tries to mend Harry's arm himself.
  The Result: Lockhart accidentally removes every bone in Harry's arm. Harry is left to painfully regrow them overnight, while everyone else in the school (except Hermione, who continues to clutch the Idiot Ball with regards to her crush on Lockhart), is given clear confirmation that Lockhart is a moron.
• Ginny's come to suspect that her diary is connected to the attacks on other students. And she's right: It's possessing her and having her set a basilisk on people. She tries to get rid of the diary by flushing it down a toilet, but later discovers that it's in Harry's hands. Not wanting him to discover her crimes, she steals the diary back. That's understandable, but her next actions really take the biscuit.
  You'd Expect: Ginny to try and dispose of the diary a bit more thoroughly than she did last time.
  Instead: She writes in it again. Granted, she probably wanted to confirm how much the diary had told Harry, but it was still a bad idea.
  As A Result: The diary has her attack two more people (Hermione and Penelope Clearwater) and Ginny herself almost dies.
• Gilderoy Lockhart is an utter fraud who uses memory charms to mind-wipe people and take credit for their accomplishments, and by his own admission is rubbish with nearly all other magic. (In fact, Dumbledore hired him because Lockhart made the mistake of hexing two of Dumbledore's friends.)
  You'd Expect: That Lockhart would turn down the offer with some of his flowery excuses. Otherwise, he is being put in a position where his immense ineptitude will be immediately apparent to anyone paying attention. He has a reputation to uphold and this is going to be a critical stain on it.
  Instead: Lockhart tries to claim that he can do any spell possible and engages in a dangerous first class with Cornish pixies. This backfires horribly; when showing off the pixies to the class, the little monsters disarm him easily. Then he vanishes all the bones in Harry's right arm, which irritates Madam Pomfrey and Harry to no end. By the time Ginny Weasley goes missing, all the teachers know that Lockhart is useless and send him on a Snipe Hunt to find the Chamber.
• Harry and Ron have figured out that the monster in the titular chamber is a Basilisk. Shortly after overhearing that Ginny has been taken to the Chamber, and then witnessing the teachers telling Professor Lockhart to deal with the monster, they decide to give him this information. When they do so, they learn that Lockhart, who has supposedly dealt with all manner of dark creatures in the past, is in fact a fraud who takes credit for deeds other wizards and witches have done.
  You'd Expect: That, since Lockhart has proven himself to be incompetent at this sort of thing, Harry and Ron would seek out the other teachers despite the orders to return to their dormitories and get them to deal with the Basilisk (Professor McGonagall at minimum). In addition, given Lockhart was about to wipe their memories and they had to disarm him, they would immobilize him in his office or make sure he's tied up securely with a note explaining the situation.
  Instead: For some reason, they decide to bring Lockhart along anyway, even though they have thrown his wand out the window and are aware he has no useful knowledge to serve of any help.
  Result: While in the Chamber, Lockhart attempts to abandon Ginny and completely wipe both Harry and Ron's minds in order to stop them revealing his secrets. They only avoid this due to Lockhart using Ron's broken wand, causing the spell to backfire on him. Even if he hadn't tried this, there was virtually nothing he could have done to help the group.
• Fifty years ago, when Riddle was a student, he opened the Chamber. Several Muggleborn students were petrified, causing a huge panic.
  You'd Expect: That the students would have been put on lockdown, the way they are when the Chamber opens in the present. Also that professors would do roll call.
  Instead: When Myrtle Warren goes missing, no one searches for her for hours. Keep in mind that Myrtle was only a kid, and she was being bullied by Olive Hornby. But even so, she was a Hogwarts student, with parents who loved her.
  The Result: Riddle kills Myrtle in the bathroom where the Chamber entrance is located when she happens to eavesdrop on him while he's summoning the Basilisk. It's unclear if anyone could have saved her from a Basilisk's glare, but maybe her body would have been found sooner. Her parents are furious and grieving, and Hogwarts nearly closes down.
  • Moaning Myrtle wasn't well-liked in life because no one tolerated her crying, and it took hours to find her body. As she mentions, she came back as a ghost to haunt her school bully Olive Hornby; the Ministry stepped in after she crashed Olive's wedding, confining her to Hogwarts. Myrtle still hangs around the bathroom where she was killed, though it's revealed she can go as far as the lake if she wishes.
    You'd Expect: That Dumbledore or someone would ask her, "Do you have any idea who/what killed you?" If he hears her testimony, it probably wouldn't be too hard to find the hidden entrance to the Chamber, as he does something very similar in the sixth book. Sure, no one had ever found it before, but he's got only one bathroom to search, rather than a whole castle, and he will prove the ability to find hidden magic, as he "knows Tom Riddle's style." Let's repeat: Dumbledore had the opportunity to interview the murder victim, a chance most detectives would give their right arms for.
    Instead: Myrtle is so unpleasant and miserable that no one wants to ask her anything; even Dumbledore fails to see past her traumatized ghost.
    As A Result: It takes someone fifty years to come up with the idea to go talk to her, and it's almost done too late to save the new batch of petrified people.
• Lockhart is trying to escape but is confronted by our heroes. He then explains how he got famous and his skill at memory charms. Then he tries to Obliviate our heroes.
  You'd Expect: For Lockhart to do this immediately because he has barely any skill in magic other than said spell.
  Instead: He reaches for his wand slower than a turtle and is held at wandpoint by Harry and Ron.
• Hermione figured out via "Eureka!" Moment that the creature attacking the students is a basilisk. She goes to the library for proof, tears out a page of a book with the information after writing "pipes" on it, and grabs a mirror to look around corners just in case. It turns out Tom cottoned on to what she was doing and wanted to stop her. He also wants to lure Harry to the Chamber to kill him personally and knows Hermione is Harry's friend.
  You'd Expect: He would leave a note with Harry taunting him to come in revenge, perhaps with Ginny writing it again on the walls where the victims are found. Perhaps a hint about a certain bathroom?
  Instead: Tom simply compels Ginny to petrify Hermione and Penelope Clearwater.
  The Result: Thanks to more restrictions, there is no way Harry and Ron can just go to Moaning Myrtle's toilet, as they figure out later that she was the murder victim. Harry also finds the piece of paper in Hermione's hand that gives him and Ron the information they need.
• Tom Riddle's ghost has returned. Harry still thinks Tom is his friend and tries to get him to help Ginny and for the pair of them to escape from the basilisk together. Tom has only a few more minutes before he consumes Ginny's life force entirely. Harry doesn't know Tom is leeching Ginny's life force through his diary.
  You'd Expect: Tom would stall for time and make sure he fully returned to life before dealing with Harry, or at least hide his diary, which is his one vulnerable spot, somewhere Harry couldn't find it.
  Alternatively: Tom could pretend to help, then subtly summon the basilisk once Harry was out of earshot, putting Harry in a position where he would have to defend Ginny, Ron, and Lockheart simultaneously.
  Instead: He immediately and unnecesarily confesses to being Lord Voldemort and the one responsible for Ginny's state. He then sics the basilisk on Harry before he is fully corporeal.
  The Result: He puts himself in a position to be killed by Harry.
• Tom reveals that he is Lord Voldemort, a specter of his young self, and that he can control the basilisk. He has also confiscated Harry's wand, leaving a twelve-year-old boy virtually defenseless. Fawkes then arrives, along with the Sorting Hat. Tom snickers that loyalty to Dumbledore brought Harry such useless assistance.
  You'd Expect: Given that Tom's ghost is later shown to be capable of magic, he would finish what he tried to twelve years ago and simply blast Harry with a Killing Curse (or any other lethal magical action he can use in this state). At the very least, he could restrain Harry like Quirrell did in book one so he can't run or wield a weapon, as well as getting rid of the bird and burning the hat.
  Instead: Tom summons the basilisk, with his orders giving Harry an unwitting Mercy Lead, and steps back to Pass the Popcorn as the giant snake chases Harry around with intent to kill. He does nothing with Fawkes or the hat.
  The Result: Fawkes pecks out the basilisk's eyes, and the Sorting Hat summons the sword of Gryffindor for Harry. Harry doesn't look a gift sword in the mouth, grabs it, and manages to fatally stab the snake while getting bitten. He gets healed by Fawkes, and only then Tom thinks of using magic against him, but not before Harry stabs the diary with a basilisk fang, destroying it and Tom along with it.