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.
Plot hole: The Jupiter 2 crew is duplicated; however, the aliens had never seen Penny (or Judy I think). How can they be duplicated? The aliens don't have ability to know who were there, or they wouldn't have questioned Smith about the crew. Also, they do not know Smith and Will are hiding. So, they don't arm to have any special power to know beyond what they actually observe.
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 Night of the Raven - S2-E3
Plot hole: Antoinette is making miniature clothes for the soon-to-be shrunken West, but when West drinks the antidote to make him normal-sized, he is wearing the same clothes which would have been shredded as he grew back to normal size.
Plot hole: In the pilot, it is established that the surface of anything/anyone made invisible by "quicksilver" is freezing. (Darien gets caught in the women's shower because the mist freezes on him. He freezes the beer mugs for the doctors.) But in later episodes, nobody notices him standing invisible - and freezing!? - next to them.
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.
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: 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: Skye's mother, Deborah, was held hostage by the Sixers for several years, though everyone believed she had died in an epidemic and was buried in Memorial Field. The Sixers kept her alive with medicine only they had to force Skye to act as their spy. Even though Terra Nova has a medical clinic staffed by doctors and nurses, it was never noticed that no one had witnessed Deborah dying, her body was never placed in the morgue, that was there no record of her being buried, or even questioned that there was no corpse. Deborah just disappeared without a trace and nobody wondered about it.
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.
Plot hole: The nuclear explosion is on Liberty Island, a small yield, but nonetheless big enough to move an enormous amount of water towards the coasts on all sides. When we see Sertrakian and the others at the harbor no water is heading their way - they should be washed away by it. (00:37:30 - 00:38:45)
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: After discovering the cards tossed into the ocean at the docks, Miss Dorothy goes to Jaden's dorm to alert him of this. There was no real reason for her to go to him, seeing as how she had no idea if this incident was tied to him specifically. (00:09:05)
The White Mountains: November, 2089 AD - S1-E13
Plot hole: The main characters are being pursued by Tripods, mind controlling alien machines. My question is, if the Tripods can turn humans into 1600's puppets, complete with foxhunts, why don't they make some of said mind-controlled humans help with the pursuit?
The Spores - S2-E7
Plot hole: Hal and Roy could not open the spore case with an electric power drill, but later a married couple pops it open with a hammer and chisel, then much later some children acquire the case and easily open it.
Plot hole: After Kara and Alex are run off the road, Kara is convinced by "Noel Neill", revealed later to be J'onn, to stop using her powers. From context, J'onn had to have been summoned by Eliza, but in 2007, she would still think he's just Hank Henshaw; she doesn't learn he's not, or even that he's a shapeshifter, until 2016, as seen in season 1's "Myriad", well after Kara and Alex have grown up.