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Star Trek: The Next Generation
... Sometimes, it's amazing that this series even had a chance to be as good as it was in season six with all the rampant Wall Bangers flying around in season one.
"The Naked Now" is the supreme Wall Banger episode in the hit-and-miss first season. The inhibition-destroying disease from the original series episode "The Naked Time" hits the Enterprise-D. During the story, Dr. Crusher is somehow unable to recognize a dangerous disease with a known history, nor does she find it in her medical database; but Commander Riker finds it in Kirk's archived Captain's Logs, which are more than 70 years old. This implies that Dr. McCoy or Starfleet Medical kept terrible records. And that is nothing when you consider that Data gets drunk off of the molecule! A sentient machine, made (mostly) of metal and plastic with a positronic brain categorically different from our own, gets drunk off of a molecule that itself only causes drunkeness because of its similarity to the alcohol molecule. The whole "Riker found what Doctor Crusher didn't" is nothing compared to that.
Data: I have pores. Humans have pores. I have fingerprints. Humans have fingerprints. My chemical nutrients are like your blood. If you prick me, do I not... leak?
By the way, Data doesn't leak: if you chop off his arm he has a snarl of wiring and metal "bones" — with empty gaps of air in between. And if you rip off or cut his skin, it just flaps there like wrapping paper, revealing the circuitry underneath. So the Trek writers accomplished the impressive feat of making even a handwave that didn't make sense actually contradict canon.
The original idea for Data was that he would have organic components inside, leading to comments like that and another where he mentions that he imbibes a form of lubricant/nutrient to keep those parts functional.
Not to mention the mutation that caused the disease to increase the libido of the crewmembers, or something. In "The Naked Time" it lowered inhibitions — Riley, proud of his Irish ancestry, imagines himself as an old High King singing love songs; Sulu, who fancies himself a fencer, becomes one of The Three Musketeers; Spock, forever forced to bury his emotional side has it come to the surface leading to him losing control and weeping; Nurse Chapel admits her love to a man who can never return it; finally, Kirk, burdened by his position of Captain, breaks down and admits the enormous pressures he's under and how being around Yeoman Rand is painful. What happens in "The Naked Now"? "You're kinda hot, let's have sex!"
However, there is a potential justification for this: The virus MUTATED. As it did, its effect must logically be altered somehow, causing a slightly different effect in most of its victims. Still doesn't excuse most of the stupidity, but at least makes this part potentially less stupid. Of course, this merely shifts the blame to the writers, who choose "Drunk people are funny" over "Let's explore the characters in depth, it'll be a good plot device to familiarize the viewers with these new characters."
In "Datalore", it's understandable for Lore to be dismissive of Wesley to slip up his disguise. But the crew is dismissive as well, causing Wesley to basically shout it out to them! And even that fails. The crew's, and especially Picard's, disbelief is inexplicable, since all Lore would need to do to impersonate Data is incapacitate him and switch outfits... which is exactly what he had done, and what he would eventually do again.
It's even worse than that because Picard had sent Wesley specifically to check on Lore and Data and see if something was amiss. Why send someone to check if something is wrong if you're just going to dismiss them when they say they saw something wrong?!
Apparently Picard had no intentions of listening to anything Wesley had to say and the order just something he gave to keep Wesley occupied, given the degree he was dismissing Wesley. Which is certainly going to set you up with a headache as to why a starship captain who apparently had a record good enough to rate captaining the flagship for the Federation would give an order like that with no intentions of respecting what the person had to say.
"Genesis": an "evolution" disease causes the crew to mutate into various creatures whose blueprints were still in our "junk DNA." Barclay turns into a spider - which shouldn't be in the DNA of anyone with a spine. Suggestion is made that Picard, Riker and Barclay (all theoretically human) don't share a common evolutionary ancestor: Picard was turning into a lemur, Barclay into a spider, and Riker into, um, Riker (Okay, an early hominid, but really, if you're going to turn one crew member into a spider, Riker should at least turn into one of the other great apes). A cat has kittens while turning into an iguana.
In "Loud as a Whisper," the great negotiator that the Enterprise is transporting is deaf and speaks through a telepathic chorus of aides. But, throughout the episode, people address him when he isn't looking by calling his name, and people speak directly to him with no-one else present, and he responds. That could have made sense if they meant mute - but they go to a lot of trouble to explain how he cannot process any sound.
Worf's big bad-ass sash is so shiny that in the Laser-Guided Amnesia episode, everyone logically reasoned that Worf must be the captain because he has the prettiest uniform. Hurrah for cultural diversity! But, Starfleet protocols forbid Bajorans to wear iddy-biddy earrings, as an episode of Star Trek: Voyager later confirms. Pretty much implying that Starfleet is okay with cultural diversity... as long as it's human, or your CO makes an exception.
There is the honored JAG from The Drumhead who hauled Picard into a Kangaroo Court for being a traitor and breaking the Prime Directive simply because he was objecting to her apparent desire to continue investigating his crew after the original problem was settled and an otherwise innocent crew member was accused of sabotage for being part-Romulan and not telling anyone. Thankfully, Picard wrecked her career by making a bold speech and tricking her into making a fool of herself in front of an Admiral. She didn't sound that much crazier then than she had all episode, though, and she had been considered honorable before, so it's a wonder it worked.
Another Wall Banger here is that she had to turn into a General Ripper to make the episode work, and cement once and for all the fact that Star Trek legal procedures were copied wholesale from the 'Ace Attorney games.
And let's not forget that partway through the trial the engineers (as in actual scientists) discovered that the explosion that kicked off the whole thing was caused by a defective seal. As in it was clearly an accident. Nobody was at fault. There was no crime. But the JAG officer is allowed to continue her crusade anyway and her assistants refuse to believe it was an accident, and purposely lied to their suspect about the cause of the explosion to try and get him to confess. Shouldn't they have been punished for trying to perjure the defendant?
I don't believe that Tarses was a defendant at that point, he was only a suspect (though, to my eye, that's even a bit of a stretch, 'person of interest' is probably more accurate based on the evidence Satie had at the time). This means that she opened what was more-or-less an interrogation to spectators. Tarsis was suspected of treason, espionage, sabotage, and perjurynote He lied in his application to Starfleet, meaning he falsified an affirmation AND SHE OPENED HIS INTERROGATION TO FRIKIN' SPECTATORS. There are so many ethical and procedural breaches here, that I wouldn't even know where to start listing them.
The episode "Contagion": the Enterprise contracts a computer virus from a ship, the Yamato, that had been infected with the virus after scanning an ancient planet for a legendary transportation technology. As a result, all of the ship's systems begin to malfunction, including turbolifts, life support, and replicators. It gets so bad that Commander Riker remarks that (paraphrase) doing anything, no matter how seemingly harmless, could trigger the destruction of the ship or its crew. So they decide to go to the planet that the Yamato surveyed to see if they can understand the program that infected them better. They then transport an away team to the surface. Problem: all the computer-operated systems are failing. So, to get to the source of the problem, you use a device which relies on the computer disassembling, transmitting, and reassembling every subatomic particle of your body WITHOUT ERROR! * BANG*
Speaking of that episode, check out Data's behavior; he throws Geordi from an electrified panel and gives a human reaction of embarrassed surprise and shock. He stupidly puts his hand through a rapidly-changing portal through space (good thing the "image" didn't change while his hand was in there). And look at his reaction to being reactivated after purging his systems of the Iconian program. This is supposed to be an emotionless android, correct? One incapable of mimicking or even understanding human behavior? Why is he acting like this?
No one in the 24th Century seems to know how to do a system restore on a computer. You forgot that there was a reason there's a protective archive in the computer core, Geordi?
"Time Squared" has a bad portrayal of both Captain Picard and Counselor Troi. Picard acts extremely emotional and forceful with everyone, including the future doppelganger of him who drives the episode. Supposedly, he's acting this way because it appears that the doppelganger abandoned the Enterprise to its doom, and the crew have no way of knowing what caused the ship to explode or why the doppelganger left until it happens. But Picard has been shown to take stuff like this more calmly in previous episodes. And even his stress can't explain why he nearly assaulted his doppelganger while he was recovering in sickbay in order to get answers, even though Troi told him several times that the doppelganger couldn't answer. Nor does it explain his rejection of the notion that the doppelganger was him simply because he couldn't see himself performing the actions the doppelganger did - especially since earlier episodes have shown him to take stuff like this more calmly and open-mindedly... Troi flip-flops on whether she's sympathetic or appalled by Picard's attitude. She goes from near-accusatory admonishment of him for his aforementioned assault, to defending his assault and rejecting the concerns of the ship's doctor about Picard's state of mind as unnecessary. So, she clearly saw how out of character Picard was and even told him off about it, but she sees no reason to be concerned about it? What kind of counselor is she? (Don't answer that last question...)
The Galaxy-class Starship is the pride of Starfleet, being its largest, most advanced, most powerful, and most capable capitol ship; and the USS Enterprise is the best of them. That's why I find it so annoying that the class in general, and the Enterprise in particular, have such a glass jaw. By my count, we have seen Enterprise destroyed no less than eleven times over eight years (Time Squared, Yesterday's Enterprise, four times in Cause and EffectTime Scape, Parallels, three times in All Good Things..., and once-and-for-all in Star Trek: Generations), only to be brought back by some combination of Reset Button and Timey-Wimey Ball-with the obvious exception of Generations. When she did finally fall, it was in a situation very similar to the one which killed her first Constitution-class predecessor. In fact, Enterprise D underperformed that ship by a laughable margin, considering Kirk's Enterprise was still heavily damaged from Star Trek II: The Wrath of Khan, was operating under heavy automation with a crew of five, and didn't actually have the capacity to raise its shields at the time-and she still managed to give as good as she got from a Klingon Bird-of-Prey.
This is a combination of Informed Ability, Forgot About His Powers, Idiot Ball, Idiot Plot, and several other induced stupidity tropes. On paper, the Galaxy Class was the most powerful ship ever built by Starfleet at the time. In practice, it was the Worf Effect embodied as a ship: whenever it was brought up that something was a match for/X times as powerful as a Galaxy Class, it was a way of setting up an unknown enemy as a credible threat. When it came down to actual fighting, the GC never did hold up very well on screen, generally firing one or two shots, and either winning or losing in those handful of shots. The only extended fight we see the Ent-D win in the series is in The Best of Both Worlds, and that is through sheer dumb luck. You could expect Ent-D to lose against any opponent she didn't immediately outclass. The Constitution-Class Enterprise, Defiant, and even the oft maligned Voyager won extended fights more than the Ent-D, and against equal or more powerful opponents far more. Part of this can be blamed on special effects of the time, as well as the cliché of how starship battles were expected to go - before Babylon 5, starship battles that weren't flat out animated were done by having a 3 or 4 foot model being filmed by a large camera that swung around at various predetermined angles, not leaving much room for freedom of movement to film the ship moving in full 3D. However a lot of this can be blamed on the fact that most Federation Captains in ST aren't portrayed as being very good at starship fighting, whatever their Informed Abilities may be. Picard is supposed to be a tactical genius, but when faced with equal opponents, he will often just fire a phaser bank or two, a spread of photon torpedoes, and get the stuffing knocked out of him until the plot intervenes. In Yesterday's Enterprise, when faced with a group of Klingon Birds of Prey that are effectively trying to stop history from unfolding as it should, Picard's brilliant maneuver is to fire 4 or so photon torpedoes at one of the ships, and get the stuffing knocked out of him until the plot intervenes. Any other non Federation modern spaceship captain (with the exception of Sisko who was an exception in that he was an effective fighter against superior odds) would have just fired at the enemy until they weren't there anymore. So yeah, Galaxy Classes suck, but they get a lot of help doing so.
Finally ended in Star Trek: Deep Space Nine. After the Odyssey gets blown away Starfleet apparently decides "Enough is enough". They stop sending single GCSs in unsupported and start using them as heavy battleships at the core of multi-starship formations, and the GCSs start winning. You haven't lived until you've seen the triumphantly contemptuous way the USS Venture blows away a Cardassian orbital weapons platform in "Tears of the Prophets".
"The Child". Deanna gets freaking raped and nobody cares. What. The. Hell.
In "A Matter of Time", a 22nd century inventor with a stolen time machine cons his way onto the Enterprise, tries to steal some future tech he can reverse-engineer, and gets caught. This isn't the stupid part. The stupid part is that they allowed his stolen time travel pod to return to the 22nd century. They solved one problem only to potentially create another. If they weren't being idiots in this scene, the proper thing would have been to send Data or Worf back with him, have him immediately return to the 24th century, then sent the pod back to its proper time.
Maybe that's the real reason there were so many continuity snarls in Star Trek: Enterprise. A bunch of primitive yokels got their hands on a time machine and proceeded to screw up every part of history they touched.