Plot hole: When teenage Prue has run away with the demon, and Phoebe and Piper find her in the park, teenage Prue is 'killed'. Her sisters drive her home to get Leo to heal her, but shouldn't they have just been able to call to Leo to orb to them when Prue was first hurt, and heal her in the park, and save driving back to the Manor and risk Prue dying?
Plot hole: In this episode Carrie runs into Aidan, who now has what looks to be about a 6 month old baby (Tate). This doesn't seem possible, as Carrie and Aidan would have only broken up about a year ago, and Miranda was around 6 months pregnant when they broke up. Brady is only about 5 months old at this point in the series, leaving Aidan only roughly 8 months to have this baby - but Aidan lay in bed for about a month and then dated Nina Katz for awhile. Timeline just doesn't seem to fit.
Plot hole: They say that whoever the sweater belongs to left it behind, but in The One Where Rachel Finds Out that Ross videotaped them together it is clear that Ross is not wearing anything under the sweater, therefore for Ross to have left it behind he must have gone home topless.
Plot hole: Throughout the show it is reported several times that Billy and Ally met when they were both eight years old in a park by sniffing each other's bottoms. However, when Billy is buried in season 3 his tombstone reads, 1968-2000, making him 32 years old. Ally is only 29 and does not turn 30 until later in that season which would at the very least, put them 2 years apart. (00:41:15)
Plot hole: At first the victim (Careful Lionel) is described as not returning to pick up his new shirt in November 1958, and possessing love letters dated from 1957 through early winter (November) 1958. Booth reports the fallout shelter where Lionel's body was discovered was sealed in 1958. Later Lionel is described as reported missing by his boss in January 1960, and the illegitimate child he fathered was born in 1960 as well. That would mean his boss didn't notice he was gone for over a year, and his pregnant girlfriend was with child for at least 14 months.
Plot hole: Niles makes up Frasier's couch to sleep in and when he lies down he lets out a yelp - and pulls a plastic pirate's hook from behind the cushions. Earlier Niles had appeared wearing a pirate's costume but at no point did he have a hook, nor did he go near the couch. His overcoat had been on the floor the whole time so it couldn't have come from there. It would have been difficult for it to get behind the cushions unless deliberately shoved there, which we never saw and makes no sense anyway.
Plot hole: During the week of Aug. 29, Taylor catches Thomas and Gabby about to make love. She then tells Gabby that Thomas is not mature enough for a sexual relationship. First of all, Thomas and Gabby are married. Secondly, Thomas is college age and can legally have sex. And to top it off, has no one told Taylor that while she was supposedly "dead", that Thomas dated and had a sexual relationship with Amber?
Plot hole: The ages of the children on the show are really inconsistent. When the show starts in 50 BC, Octavian is around 12, Lucius is an infant and Vorena the Younger is at least 8 (given that she must have been concieved before Vorenus left for Gaul). Three years later Caesarion was born. When Simon Woods takes over the role of Octavian, Octavian is around 19, as stated on the show. Lucius should be seven but looks like he's four and Vorena should be fifteen but still looks eight. Episode 9 of season two takes place in 32 BC, 18 years after the first episode. Octavian might very well be 30, but Lucius (who would be 18) is around seven, Vorena (who would be 26) is a pre-teen and Caesarion (who would be 15) is around eight. Even if the events were moved up so that episode 9 is actually set earlier, the ages of the children still don't match when compared to how much the other characters have aged.
Plot hole: In the bait and switch section, why does anyone involved agree to Leland being Ben's attorney when both victims are relatives of Leland? Neither Ben nor any of the police are in on Cooper's plan, and it seems implausible at best that they would agree to this.
Plot hole: Bonnie is the anchor for the other side and feels when supernatural beings die. How come she didn't know Katherine wasn't dead? Did she never think it was suspicious that she never felt Katherine's body after she died?
Plot hole: The mob hitmen are about to enter the Sweeny family's house to kill them when the police van arrives to move them to a witness protection safe house. In the next scene, the bad guys abduct Catherine and try to force her to reveal where the Sweenies have been taken. Why? They could very easily have waited and simply followed the van. (00:36:30)
Plot hole: In the lab when Liz makes the slides of her cheek cells and the cells from Max's pencil, the first time she doesn't add stain and the second time she does. If she's going to be a molecular biologist she really ought to learn to apply techniques consistently. (00:07:30)
Plot hole: In the end of the episode, Wolverine is seen recuperating after surgery removes the microchip in his brain, and his head is bandaged. Performing invasive surgery on Wolverine's brain isn't possible, since that would require going through his adamantium-infused skull and no conventional material is capable of that. Only a less invasive technique (such as going through the cranial sutres or cranial foramen) would have been effective and that most likely would not have required Wolverine's head to be bandaged (especially with his rapid healing mutant ability).
Plot hole: The plot gets confusing here. First, Laura and Jack (the dog) are rabidly bitten by Jasper (her pet racoon). The doctor warns they may have rabies from the bite. A second more dangerous raccoon is discovered which eventually left the area. In the end, Charles (discovering there were two raccoons in the barn after finding Jasper remaining), says Laura is going to be OK after all. The main confusion is that Laura would still be in danger from the bite regardless of which untested raccoon bit her.
Plot hole: Noah cancels the club's scheduled Monica concert because Dylan pays him to have her give a private performance to Dylan and Gina instead. He seems really excited and proud of himself for some reason. Even if Dylan paid him much more than he would have received from the gate (which is likely), this could cost Noah money in the long run. Many customers would probably get angry and decide to stop frequenting a place that would cancel a concert at the last minute for no good reason. Then again, Noah was never exactly a genius - in business or otherwise.
Plot hole: In Pemberley, Caroline Bingley refers to an utterance of Darcy ("I should as soon call her mother a wit") that he made after coming home to Netherfield after their first ball in Meryton. Falsely she says he made this expression "after they had been dining at Netherfield". This is a direct quotation from the novel and is not coherent with the film plot in which this utterance is made after the first ball.
Plot hole: In this episode, a very star-struck Paul meets Jerry Seinfeld on the street. It's not clear whether Jerry is playing himself or his Seinfeld character, but either way it's a mistake. If Jerry was playing himself, it's a mistake because Mad About You did a crossover episode with Seinfeld in its first season, so it would be impossible for Seinfeld (the TV show) or Jerry Seinfeld the actor to exist in the Mad About You universe. If Jerry was playing his character, it's a mistake because it was established in that crossover that Paul and Jerry used to be neighbors and knew each other fairly well, so Paul wouldn't be at all star-struck.