History YMMV / TheDemonHeadmaster

** Dinah, Harvey and Mrs. Hunter finding Lloyd comatose after he was stung by the KillerWasp. Mrs. Hunter's reaction can really hit home for any parent who's suffered a similar experience.

* TearJerker: Dinah's brief HeroicBSOD after snapping at Mrs. Hunter in Episode 4.

* MoralEventHorizon: we all know that Rose, being the de-facto leader of the Prefects is strict and all, but she crosses it when [[spoiler: she punishes Lloyd, Harvey and Dinah by making them shovel snow (without their coats on), and to top it all off she and the prefects push the trio in the snow not caring about Harvey's asthma.]]

* SugarWiki/AwesomeMoments: The original Demon Headmaster appears in the final episode of season one of the 2019 series, revealing himself to be the real BigBad of the series.

* WhatAnIdiot: In ''Takes Over'' it turns out that [[spoiler: the Headmaster, being a clone of the original, has lost many of his memories, including what his name is, which prevents him fully taking control of the Hyper-Brain computer because it wants to know his name before giving him full access]]. Instead of just [[spoiler:making up a new name for himself]] he comes up with a convoluted scheme to lure the SPLAT members to the laboratory so that they can [[spoiler:''tell him what his name is'']]. Naturally, this leads directly to his defeat at the hands of the group. It's a little less blatant in the TV series, where he knows that Dinah isn't likely to directly give him the information that he wants, and so his intention is to have the Hyper-Brain absorb her mind and then obtain the information that way.
** In the character's defense, considering the Hyper-Brain's access to other networks, [[spoiler:it may have at least identified the original Headmaster through its contacts, thus justifying its need to have him identify himself by the name it 'knows' rather than accepting him just making up an alias]].

* {{Tearjerker}}: Dinah's brief HeroicBSOD after snapping at Mrs. Hunter in Episode 4.

* WellIntentionedExtremist: The Headmaster's schemes are focused upon creating and maintaining order and efficiency...at the expense of democracy and freedom.

* WinBackTheCrowd: The decision to have [[spoiler: Dinah]] appear in the new series for those that complained about the new books not featuring SPLAT.

* {{Fanon}}: Many people have interpreted the eponymous character as an alien, in no small part due to his hyponotic abilities and the fact that his eyes are green.

** In the character's defence, considering the Hyper-Brain's access to other networks, [[spoiler:it may have at least identified the original Headmaster through its contacts, thus justifying its need to have him identify himself by the name it 'knows' rather than accepting him just making up an alias]].

* WhatAnIdiot: In ''Takes Over'' it turns out that [[spoiler: the Headmaster, being a clone of the original, has lost many of his memories, including what his name is, which prevents him fully taking control of the Hyper-Brain computer because it wants to know his name before giving him full access]]. Instead of just [[spoiler:making up a new name for himself]] he comes up with a convoluted scheme to lure the SPLAT members to the laboratory so that they can [[spoiler:''tell him what his name is'']]. Naturally, this leads directly to his defeat at the hands of the group. It's a little less blatant in the TV series, where he knows that Dinah isn't likely to directly give him the information that he wants, and so his intention is to have the Hyper-Brain absorb her mind and then obtain the information that way.

* NightmareFuel: Some of the [[https://images-na.ssl-images-amazon.com/images/I/41o0Bqnf2zL._SX285_BO1,204,203,200_.jpg front]] [[https://images-na.ssl-images-amazon.com/images/I/51McfajTjXL._SX313_BO1,204,203,200_.jpg covers]] [[https://images-na.ssl-images-amazon.com/images/I/41VCH12BQ3L._SX302_BO1,204,203,200_.jpg of certain editions]] of the books are pretty disturbing to look at. [[TheFourthWallWillNotProtectYou It's easy to believe that]] the Headmaster is actually staring at you, the reader.

* NightmareFuel: Some of the [[https://images-na.ssl-images-amazon.com/images/I/41o0Bqnf2zL._SX285_BO1,204,203,200_.jpg front [[https://images-na.ssl-images-amazon.com/images/I/51McfajTjXL._SX313_BO1,204,203,200_.jpg covers]] [[https://images-na.ssl-images-amazon.com/images/I/41VCH12BQ3L._SX302_BO1,204,203,200_.jpg of certain editions]] of the books are pretty disturbing to look at. [[TheFourthWallWillNotProtectYou It's easy to believe that]] the Headmaster is actually staring at you, the reader.

* UnfortunateImplications If you watch the TV show as an adult it suddenly has a very creepy subtext when the Headmaster lures Dinah to his office and then hypnotises her. Especially since she can't remember what's happened to her.

** What's worse is that he's able to use technology to the same end, meaning you don't ''have'' to see him.

* WhatAnIdiot: [[spoiler: In ''Takes Over'' it turns out that the Headmaster, being a clone of the original, has lost many of his memories, including what his name is. This prevents him fully taking control of the Hyper-Brain computer because it wants to know his name before giving him full access. Instead of just making up a new name for himself he comes up with a convoluted scheme to lure the SPLAT members to the laboratory so that they can ''tell him what his name is''. Naturally, this leads directly to his defeat at the hands of the group.]]