Plot hole: When Bryce's body is found, there is a gaping hole in the back of his head, leading to speculation that he was shot. It is later determined that the hole was from blunt force trauma. However, when we actually see his death, he is simply pushed off the pier and ends up drowning. It wouldn't have been caused by his fight with Zach, as he would have been dead long before he could have been pushed into the water. And if the wound was somehow caused by aquatic predation, the forensics experts would know the difference between that and blunt force trauma.
The Man Who Was Never Born - S1-E6
Plot hole: Andro has memorized "every detail" of Cabot Jr.'s life, including his mother's name, Noel. Yet when he travels to the past, meets Noel and learns her name, he still mistakes Cabot Sr. for Cabot Jr., who isn't born yet. Having memorized all those details, he would have known the moment he met her that Noel was Jr.'s mother. Andro's confusion makes no sense. (00:28:00)
Plot hole: If the electrical lights go out at a quarter past ten at Guardbridge, how come there is bright electrical (as suggested by it not flickering like candle light) light coming from a room behind Hal Stanton and Catherine Faulkner when they kiss? This scene takes place after 22:15.
Plot hole: Dr. Adam Soong is initially presented as a discredited scientist, banned from the scientific community; he gets debarred and his funding revoked. And it's not an internal matter; he is publicly exposed for it. His daughter in episode 6 even finds out this information on Google. Several news articles call him "mad scientist" and such. However, this same person at the same time throughout the rest of the season has every bit of pull and influence, not just through undercover channels, but is treated with the utmost honor and deference by the NASA PR people at public events.
Plot hole: Ruth enters Darlene's home at night, crossing over the crime scene tape. She proceeds to the barn where she finds all of Darlene's heroin packed up neatly. This is factually impossible. Once the police had secured the crime scene in the house, they would have searched the entire property and would have discovered and seized the heroin at that time. (00:54:38 - 00:56:09)
Whatever Happened to Sarah Jane? (1) - S1-E8
Plot hole: When Maria Jackson is running away from the alien creature, she turns left into a metal fencing. The camera shows this seconds before she runs into it, banging on it in frustration. This does not make any sense. She saw the metal fencing, so why did she continue to run into it? Why did she not turn right instead and along the park?
Casus Belli - S6-E5
Plot hole: Later in the evening, after NYPD takes Quinn into custody, Carrie finds his cell phone, with pictures showing their home had been spied upon from across the street, as well as other evidence of a conspiracy. He had tried to hand her the phone right after the police broke in, but it was knocked from his hand and she discovered it under the smashed door. In the real world, Carrie's home would have been considered a crime scene and the police would have searched it thoroughly, top to bottom, undoubtedly finding the phone themselves, but are shown driving away after the confrontation.
Over My Head - S3-E4
Plot hole: Daphne was able to hurt Duke because his name appears on her cell when he called, but names only show up on a cell phone if the person's number and name are programed into the phone, and Duke has already said he doesn't know her.
Plot hole: In the Pudding Club episode, when they visit the secret room, all the candles are lit even though no-one is in there.
Plot hole: Lucien, Trustan and Aurora are somehow compelled to believe they are Mikaelsons, when no-one knew how to compel until Elijah compelled Aurora by mistake when they fled. So when did this supposed compelling happen? Did Elijah go back and do it later on? The siblings all had knowledge of him compelling them, so I'm confused exactly when they all learned of their ability.
Plot hole: White Base and the interior of Luna II withstand without a scratch the explosion of the thermonuclear reactor from the Magellan from just a few meters, while the blast literally vaporizes the Zaku far away from the entrance and threatens to damage the Musai, hundreds of meters away.
The Daughters of Jerusalem - S2-E6
Plot hole: Dinah Fortescue's fingerprints are supposed to be on a teacup but she's wearing gloves in the flashback. So how did they get there? (00:24:35 - 00:33:34)
Plot hole: Matlock figures out that The Professor wouldn't have been able to see the security guard from 50 yards without glasses, and that's what tips him off about The Conspiracy: the guard testifying that the man wasn't wearing any. However, when we see the scene happen at the beginning of the episode, the person posing as Prof. Erskine Tate is, in fact, wearing glasses. (00:04:15 - 00:22:15)
Plot hole: If Andy really did enlist into the Army Reserves and "forgot about it" like he claimed a warrant for his arrest for desertion would have been issued, which the police would have seen when he was arrested for pot possession in the episode "Lude Awakening." After seeing the warrant, the police would have called the Army, and he would have been returned to military control to face desertion charges. He would not have been released and sent a letter a few weeks later simply telling him to report for duty or face military prison; the option to report for duty would have no longer been available when he was gone long enough to get put in deserter status.
The Aptitude Test / Oskar Gets a Job - S3-E9
Plot hole: Mr. Simmons asked that each student put their name on the test folders, but the folders already had names on them when he handed them out.
Plot hole: When Two-Face and his men have broken into the new D.A.'s office to find dirt on Rupert Thorne, one of his men finds a file detailing Thorne's record of Swiss bank accounts, money laundering, blackmail and payoffs that Two-Face tried for years to subpoena when he was D.A. When Thorne finds out that Two-Face has the file, he states that he will be ruined if Two-Face gives the file to the police. If Two-Face tried unsuccessfully for years to subpoena the file, then in all likelihood that means Thorne paid off the right people to prevent the subpoena from happening, so Two-Face giving the file to the police shouldn't be a problem for him. Additionally, if giving the file to the police would be all that it would take to bring Thorne down, then the new D.A. could have already done so. If the new D.A. was also paid off by Thorne, then it wouldn't make sense for Thorne to allow the D.A. to keep the file since they could easily lose the file or even double-cross Thorne. (00:10:45 - 00:14:20)
The Bank Job - S3-E1
Plot hole: When Toby, McCluskey, and the others are looking at the bank's security camera footage, Toby asks to zoom in on Newman's tattoo, and then Toby asks if he can borrow someone's cell phone so he can ask Oz about the bank manager. It cuts to Oz at the hospital as his cell phone rings - when Oz picks up his cell he presses the button and promptly says, "Hey, Toby, what's up?" It's quite impossible for Oz to have known that it was Toby calling him if Toby was using someone else's cell, and he did not even have the chance to hear Toby's voice. Those telepathic abilities belong to Toby, not Oz.
Plot hole: When Nicky goes into prison in Mexico to give a criminal a shot of insulin, two errors are seen. 1) The needle and syringe are far too big for an insulin shot, which takes a one ml syringe and a small sub-cutaneous needle. 2) When we first see the syringe, there is a small amount of insulin in it, but it grows the more times we see it, until a large syringe is two-thirds full - insulin is enough in a one ml syringe.
Plot hole: The demented villain is not keeping tabs on the elevators! The rescue teams can move freely around the tower, the elevator doors can be pried open with ease like Sophie and her husband do, so his threat is completely empty and ineffective, somewhat surpassed in idiocy only by Batwoman's response, who during the ultimatum gets back home and keeps busy spraypanting the suit and finding a wig for her date with the crazy guy at the top of the hour rather than taking 10 minutes or so to free the people trapped in the 7 elevators first, unopposed as she is, and go challenge the idiot later when he has no more hostages. It shoud also be noted that the villain made the "hostage" situation and the "one hour" ultimatum known only to Kate! The police and the Crows have no reason at all not to intervene with full force to check out who the crazy bomber guy is, but the police does not swarm the building and nobody finds odd to see a madman on top of the building under terrorist attack.