Morale is appropriately grim at the Springfield Nuclear Power Plant - after all, when you're owned by a money-hungry 104 year old who holds employee raffles to be "industrial chimney sweep for the day", odds are there aren't a lot of reasons to be happy at work. And when Marge is hired to work at the plant after the Simpson's house begins to sink and they need some extra money, she takes notice that a few of her co-workers are looking a little depressed.
And while "weeping uncontrollably" and "staring into the abyss while binge-drinking" are dark in and of themselves, it's the third employee Marge notices that should have set off a few more alarms:
Yep - one employee is polishing his double-barreled shotgun and loudly stating that he is the "angel of death" (to no one in particular). This is not-so-subtly indicating the guy is on the cusp of shooting up the whole power plant indiscriminately - and Marge's solution is to have a silly hat theme day and pipe in some Tom Jones music.
...which expectedly does nothing for the incurable depression felt by Marge's co-workers, and even LESS for the potential mass shooter, who now seems VERY EXCITED instead of stoic about his plans. Oh, and then he cocks his shotgun (now pump-action instead of double-barreled) and heads off into an unseen future:
And given how Burns has dealt with dead people before, it's not a stretch to assume Smithers and he disposed of whatever dead bodies were left in the mass shooter's wake.
Principal Skinner almost pulled off one of his savviest moves ever - inviting every troublemaker in Springfield Elementary to a tiny, locked room with a promise of free mountain bikes in order to hide them away while Superintendent Chalmers did his scheduled evaluation of the school. It's a little trick the Springfield Police would later use (to much more success) later on with motor boats:
And at first, Skinner's plan works like a charm - the troublemaker students are dim enough to not recognize the scheme, and they find themselves trapped in a tiny room, with only Principal Skinner aware of their predicament.
Unfortunately for Skinner, Bart is able to sneak out of the room...but instead of helping his co-troublemakers out of their situation, his inclination towards tomfoolery leads him to screwing up the Chalmers visit and incurring Skinner's wrath with expulsion. And Skinner, so enraged by the sudden turn his day took, forgets about the other kids trapped in the room entirely. For 8 days straight.
8 days alone in a tiny room, mostly filled with nothing but chemical toilet, blankets, and crackers.
It eventually occurs to Skinner what he's done and he rushes back to the school to give the kids their mountain bikes so no one sues him. Unless, of course, they're already dead (which would be the most likely situation, honestly):
In a complete stroke of luck, the kids DID survive - somehow making due with nothing but crackers and old candy bars, it looks like. It's unclear what they did for water in this time, but given their only options for liquids were probably their own urine and those barrels of chemical toilet, maybe it's best we don't know for sure.
Homer's been needlessly mean to Flanders before - hell, that's pretty much the only way to sum up the entirety of their relationship - but maybe the furthest Homer's ever taken his disdain for Ned is when he was planning to bash him over the head with a lead pipe and steal his tickets to a football game. Of course it's important to preface this by saying that Ned had offered to give Homer one of the tickets for free beforehand, to which Homer slammed the door in his face and cursed god (or rather, a waffle stuck to the ceiling that Homer mistook for god).
So when all other avenues for getting tickets to the sold out game dry up, Homer decides to sneak over to Ned's house, ring the doorbell, and raise a lead pipe for when he answers the door (at least, HOPING Ned would be the one to answer the door - there's absolutely a chance it could have been Maude, Rod, or Todd who greeted Homer).
When Ned does eventually open the door, Homer reluctantly decides to accept Ned's offer of a free ticket and DOESN'T hit Ned in the skull with a pipe - but it's indicated that Homer gives up on his plan primarily because Marge caught him in the act, not because he had any hesitation about assaulting/killing his innocent neighbor.
And worse, Ned is KEENLY aware of what Homer was planning, and just laughs it off as a silly joke or something.
Of course, later on we'll find out that Ned's gentle good humor over Homer's despicable acts and schemes may have been masking something...
This is probably as far as I'm willing to venture into the later seasons of The Simpsons - the season 12 episode Skinner's Sense of Snow, which isn't really a great episode or anything, but does include one of the most uncomfortable jokes I'd ever seen on The Simpsons, bar-none: Homer, high on car exhaust fumes, mistaking Bart for an Arabic temptress and trying to force himself on his own son.
You see, earlier in the episode the fumes had caused Homer to hallucinate that he was a sultan, surrounded by a variety of attractive women dancing around him and drenching him in a ranch dressing hose:
...so when the car begins to fill with exhaust fumes again, there's some precedent to what Homer hallucinates - another beautiful woman, except this time, it's Bart (and Lisa, thankfully for her, is just a camel):
The creepiest and darkest part of this is that previously, Homer had fantasized/hallucinated about obviously beautiful adult women...but this time, his fantasy woman is literally just Bart in a wig and makeup. He doesn't envision Bart as a beautiful adult woman, just as himself with some slight alterations...and then he tries to kiss Fantasy Bart:
And while you can forgive SOME aspect of this, due to Homer being incapacitated by being high on fumes, it should be noted that in this state he's aware that Bart is struggling to push away his father's sexual advances...and he brushes it off. Just imagine this from Bart's point-of-view - his father is high on fumes and desperately trying to kiss him (while allowing the car to veer wildly and dangerous on an icy road. It's hard to envision a weirder, scarier situation than THAT.