Plot hole: Cadmus sets a brain-controlled Connor loose in public, without apparently remotely considering the possibility that anything might go wrong. When he regains control all they've got is a few goons onsite armed with regular ammunition - what did they think that would achieve? They know exactly what he's capable of. Either have kryptonite ammo or don't bother having anyone there at all.
Don't Let the Good Life Pass You By - S3-E8
Plot hole: When Janet and Michael visit Doug Forcett, they realise his lifestyle, like drinking his own urine and only eating lentils and radishes, is not the "blueprint" they imagined. However, Janet should already have known all of these details, due to knowing everything about everyone in the universe, so a) she could have told Michael this without visiting Doug, and b) she should not have been learning all this for the first time herself.
Plot hole: WARNING SPOILER AHEAD. The alien impersonating Skokes changed the ship's destination to Earth. This is impossible to have been done, as the first order the captain gave was to lock the course in and "Skokes" admits his security clearance was removed after his rescue from his prison. It also couldn't have been done by another alien spy, as no other survivors beyond the 4 (2 human and 2 aliens) were found and the only other alien spy was unconscious, so he couldn't have helped out in any way.
Plot hole: During "the changes" people fear machinery, but the woman who pulls back her curtains to watch Nicky and the sikhs go past is wearing a watch.
Plot hole: This was the first episode of the series and we see that the rangers are unable to figure out how to properly operate their zords; but in Origins Part 1 (which takes place prior to this) they have no issues with the zords at all.
Espa Roba: The ESP Duelist - Part 1 - S2-E9
Plot hole: Joey attempts to summon Giltia the D Knight, but is unable to because it is a Level 5 monster and monsters with that are at least Level 5 require the player to sacrifice one of their monsters that are already on the field. This is a new rule that Kaiba implemented as part of the tournament which Joey didn't know about, but in the previous episode, he watched Yugi sacrifice a monster to summon Summoned Skull, so he should have known this. (00:06:10)
Plot hole: As the first prisoner is being pulled towards the organ cutter, you see on the wall the exact shape of the body organs for the brain, lungs, heart, liver, stomach, kidneys and testicles/ovaries that serve as guides and a track for tiny saw blades to come out and cut into the person's body to harvest these organs. The problem is these are in a fixed position, which might work for some people. However people are different sizes, shapes, and heights and most wouldn't match up to these blade guides. So a good majority of the people they cut apart to harvest organs out of wouldn't even give them good ones as the blades would cut into the organs and ruin them. (00:25:20)
Plot hole: The White Knight is knocked out by a bomb in his attack on the casino. When he regains consciousness, he fires one last crossbow shot, which he thinks destroys the casino. But who loaded and cocked the bow for that last shot? Crossbows don't reload themselves.
Plot hole: During Ryder's report, as Bruce and company watch it on TV, the camera suddenly zooms in on Joker standing on a catwalk above Ryder, and none of the crew, especially not the camera man who caught the villain, makes a comment about this. They may have thought the Joker (or rather an impersonator) was perhaps a surprise gag in the show, but since this is supposed to be a serious documentary report, it is still strange that they wouldn't point it out.
Plot hole: I believe in the very first episode, during the flashback when Mick remembers rescuing Beth and killing Coraline, we see him stab her with a wooden stake, which is supposed to paralyze a vampire, as said in the "Dr. Feel Good" episode. However when Mick looks back with Beth in his arms, Coraline suddenly gets up and watches him leave while burning to "death." This is simply not possible; in the "Dr. Feel Good" episode, Mick could not release the stake himself and asked Beth to do it. This also happened in the episode when Josef was staked by the hit man that was hired to kill him, (in the episode where we meet the woman, Sarah I believe, that he accidentally put into a coma after attempting to turn her). Again, Josef was unable to remove the stake himself and Mick had to do it for him, so there is absolutely no way Coraline would be watching Mick and Beth leave; she would still be on the ground possibly burning to death.
The Beacon - S1-E26
Plot hole: Barrows introduces himself as "Dr. Dennis Barrows," and Teddy asks, "What's a doctor?" As the isolated villagers have never heard of doctors, Teddy would have no way to know that "Doctor" was a title/profession and not simply part of Barrows' name. He should have asked, "What kind of a name is Doctor?"
Plot hole: Dillon was quickly identified by the city sensors as having metal parts, thus classifying him as a threat to the city. Yet Tenaya, who is essentially a cyborg, tries out for the Green Ranger without setting off the same sensors.
Suggested correction: Tenaya wasn't caught because the guards assumed the equipment was faulty. It was giving positives all day because of all the sleeper agents we find out about later.
Plot hole: The way slipstream works is wildly inconsistent across the show. Sometimes, they have to travel a significant distance to find the nearest slip point, and other times, when it's required by the plot, there's a slip point conveniently right next to the ship.
Suggested correction: How is this a mistake? Unless the points are evenly distributed and all close to each other, they are going to be different distances away.
The Feminum Mystique: Part 1 - S1-E5
Plot hole: If her younger sister Drusilla is sent from Paradise Island to retrieve Diana, how did she get to Washington DC or wherever, she had no way of knowing where her older sister would be.
Into the Mouth of Evil - S2-E23
Plot hole: While fleeing the guru's disciples through a narrow side street, Jackie gets cut off by the van driven by Dr. Jamba and associates, stun-sprayed in the face, and then loaded into the van. But with three brutish-looking guys being so close to their quarry, the real crooks can take the time for dragging Jackie around to the back door instead of loading him through the side doors?
Plot hole: Sydney is able to surmise from the artwork (we could also say from the writing, but her rival is one step ahead of her for 2/3 of the episode and it is established that he does not know the language) the precise location of the koi in Lumbini. The map is 150 years old, but there's no way even with a big stretch of imagination to buy that they both'd be able to pinpoint with such ease and certainty its location in the basement of a random building in the bustling market center of a town, that surely changed plenty during the past century and that does not bear any special landmark.