The Signs in the Silence - S6-E21
Stupidity: Bones realises she could pull a wisdom tooth from Amy in order to identify where she grew up and find her birth parents. Which works, but at no point do they consider simply going through missing person records with the relevant info. They know how old she is, they know roughly when she disappeared, not like there are hundreds of 3 year olds going missing every year, especially not with Waardenburg syndrome. By that age her deafness would have been apparent, which would narrow the pool hugely.
Camp Redwood - S9-E1
Stupidity: Brooke leaves her apartment window open as she sleeps, even after telling her friends that serial killers (like The Night Stalker) strike during the summer when everybody leaves their windows open.
Stupidity: The Tomorrow People tend to enjoy walking into and walking out of most scenes rather than teleporting. In particular, when fighting and needing to run away, they'll teleport to get a better fighting vantage instead of teleporting out of the situation.
Stupidity: On 8/12/04, Hope specifically told everyone that when the coin was thrown into the force field, there would be a bright flash and that they shouldn't look at the forcefield when this was done. But all three times that the coin was thrown at the force field that day and the next, everyone looked right at it the whole time, and then recoiled in pain at the flash that inevitably occurred.
Two Hundred Dollars and a Bus Pass - S1-E8
Stupidity: Two police officers and a physician find an injured woman in a lab. The officers attend to the woman while the physician calls for EMTs. Wouldn't it be better if the physician looked after the injured person while the officers called for help?
Stupidity: An explanation is given for the reason why the bombs planted on the Gundam are not activated by remote control (they have plastic explosive in the regiment but not remote controls!), but no reason why they set the timer for the explosion to 30 minutes, way too much to be of any use in combat against the Gundam. Moreover, if the vulnerable spot of the Gundam shield were situated where it explodes at the beginning, it'd be completely useless.
Stupidity: "Rei" comes into the circle, having been champing at the bit to "turn him into a smear on the floor." She's wielding a sword, Kovacs is unarmed, and she...slices him a bit, instead of a quick killing blow.
Who, What, Where, Wendigo? - S2-E10
Stupidity: Dwight, Audrey, and Nathan all know Dwight's trouble is that all bullets are attracted to him, so why is he with them when they go looking for the killer, knowing every one is using a gun?
Stupidity: Amazing how people on this show, like The Accused here and in the earlier episode "The Chef", are leaving their doors unlocked or no explanations given as to how the actual killer planted the evidence.
Ayaushi shiryu! Cloth no hakaba - S1-E10
Stupidity: Saori blushes when Seiya opens the door shirtless...but she's seen him shirtless practically all her life, the boys kept training and fighting all the time. He even fought shirtless for the last part of his duel with Shyriu just the day before.
Episode #1.2 - S1-E2
Stupidity: The part when the Colonel and the governess pose as journalists does not make sense. It's far-fetched enough that after a lengthy interview about the culprit's fortune the topic of his family never came up, considering it was one of the main goals and an ideal question to lead with, but considering that "mr. Todo" does not want a picture taken and has a tight security, there's no way that a photographer carrying a large 1930 camera would have been allowed into the interview room to begin with.
Backlash of the Hunter - S1-E1
Stupidity: Rockford knows almost nothing about the guy who is tailing him except that he noticed him while he was grabbing a bite with his client. Regardless of that, he sends the same client to seduce him, just assuming that he won't be able to recognize her. And it works. Is Lindsay Wagner this hard to forget, that this guy just an hour or two later isn't able to tell it's the same woman his target was meeting?
He Lokomaika'i Ka Manu O Kaiona - S8-E20
Stupidity: After being stripped of their weapons while looking for terrorists in the jungle, Steve and Catherine meet up with Jerry, who has not had his gear taken, but didn't bring a gun because he's only a consultant. Some time later, after they open some coconuts using a small machete Jerry had on him, they hear gunshots, and go over to investigate, finding two dead hunters. They take a pistol of one of the hunters right before encountering the terrorists. So far, so good. But then to fight the terrorists, Steve has Catherine provide cover fire with the handgun while he attacks them unarmed, and hands Jerry a rock when he asks what he's supposed to do. Why doesn't one of them take the machete? You can still see it on Jerry's back.
Episode #1.7 - S1-E7
Stupidity: When Eugene approaches Tsuda after Tsuda is shot by Ae-sin, Tsuda attempts to shoot him, but after pulling the trigger, he realises there are no bullets in the gun. Seconds later, a group of soldiers run up to him, and he attempts to shoot them, but he can't because the gun is still not loaded. Something he should have known since he only just attempted to shoot Eugene and failed because of it. (00:50:00 - 00:50:30)
Stupidity: After Bernie discovers a treatment for the infection, radiotherapy, everything goes back to normal. Except the contagion is airborne (which is why they were going to flush the entire ship's atmosphere), so they're just going to re-infect themselves in a few hours. And there's only one room on the ship that can be exposed to stellar radiation, so there's no way to clean the atmosphere either.
Stupidity: Roberto Hongo is the center forward of the Brazil national team, and as we see from Tsubasa's poster/magazine, he did not alter his appearance except for wearing a fisherman hat sometimes. Despite being surrounded by football fanatics, he manages to keep a fairly low-key profile and it's totally not a big deal to have a top tier footballer hanging around the small prefecture.
Log 81: The Long Walk - S1-E14
Stupidity: They are looking for a red convertible. No other description of the car. A red convertible pulls up behind them and passes them. The ragtop roof is up but it's still matches the description. Doesn't faze them in the least.
Stupidity: While discussing his arrest with Emily, Seth mentions that he didn't tell the arresting officer that he works for Kirkman. As the White House's liaison to the media, Seth has a high degree of visibility; it would extremely difficult, if not downright impossible, to keep his place of employment concealed from the police for very long in the time between his booking and arraignment and when Kendra bails him out the following day.
Stupidity: Throughout this entire show, there is almost ZERO explanation of how, in such a small town, murder, assault, battery are committed by the club with no mention of HOW they're able to do so. This is with DNA, a barrage of ATF agents (in the beginning), and let's assume a forensics lab in the entire state. Has anyone seen forensic files? I mean come on, in the 80s in cities 100+ larger they were able to solve crimes.