Continuity mistake: From the outside of the house, you can see the staircase and door are to the far left of the house. But from inside the house, you have a fireplace and the staircase to the right of the door. So you know it's not the same house they use in the show.
Funeral at Fifty-Mile - S1-E22
Continuity mistake: When Jessica walks from the house to the barn at the end, she is wearing knee high brown boots. By the time she reaches the barn they have been replaced with court shoes.
The Night Dr. Loveless Died - S3-E4
Continuity mistake: In the opening scene, a cowboy sitting atop the balcony above Big Brad's Bar gets up and approaches the balcony's edge twice.
Continuity mistake: When Megan is running late to pick up her daughter and friends from a sleepover, she arrives in the medical examiner car with Peter. The girls walk towards the car. Megan then gets out and introduces herself to the friends. The girls dump their bags on the ground and the two friends go to get in the car. Her daughter stands by the bags and asks 'who are you?!' to Peter. He explains who he is and that he works with her mum. - however in a previous episode her daughter goes to her work place and interviews all the staff, including Peter. (00:17:35)
Continuity mistake: In the scene explaining the history of the missing jade elephants, they are described as being given to ambassadors by the emperor Zhu Di of China when the Forbidden City (in China) was first opened to foreigners in 1421. When the elephants are all brought together, the representative Daichi Yoshida from the Japanese embassy comes to pick them up, describing them as "a priceless piece of our history."
Episode #1.3 - S1-E3
Continuity mistake: Vera fires the gun several times, and later tells Justice Wargrave that the gun is empty, meaning that all the cartridges in it would be spent. When the judge loads his one bullet into the chamber, he does so in a gun where all five cartridge svisible are unspent.
Chapter One: The Vanishing of Will Byers - S1-E1
Continuity mistake: When Will is being chased by the monster and runs into his garage, he pulls down his .22 rifle hanging on a wall rack. After he loads a few rounds aiming it at the door, the monster appears behind him. After Will and the monster disappear, the scene shows his rifle is back on the wall rack in its original spot. Did Will or the monster place it back on the wall rack while Will was being abducted? (00:07:25 - 00:08:10)
Free for All - S1-E4
Continuity mistake: Throughout the episode, Number 6's lapels switch from having solid to broken white piping and back again.
Continuity mistake: When Raymond brings the doctor his milk and pill, the tray with the milk and pill are already on the bedside table.
Girl Trouble / School Dance - S3-E18
Continuity mistake: Besides the fact that when Helga is sharpening her pencil, the desk arrangement changes, one of the students visible when she looks at Arnold is... Helga. This happens because the shot is taken from the episode "Helga's Love Potion."
Continuity mistake: When Buffy is talking to Riley, she puts the scarf on her head, on his hand. He talks to her and says "Maybe I am the bad guy," and in the next frame her scarf is back on her head again, then off again in the next frame. (00:24:20)
Continuity mistake: Right after Cordelia has her vision, Wesley goes to the whiteboard. In the "Case" column he writes "N.D.U.O." Underneath what looks like "CARYNSS" crossed out. But once they find out that it is a Prio Motu demon and Angel writes it on the whiteboard, "N.D.U.O." disappears even though Angel did not rub it off.
Continuity mistake: The age gap between Eric and Cory decreases as the series progresses. At the start of the show, Cory is in 6th grade and Eric is a high school sophomore, meaning they are four years apart, give or take a few months. By season 3, Cory is in 9th grade (confirmed by dialogue mentioning that Shawn, who is in the same grade as Cory, is 15 years old), and Eric is a senior, leading to an age gap of three years. The first episode of season 4 takes place a couple months after the end of season 3, with Eric and Cory returning from a summer Road Trip, but just two episodes later, Cory mentions that he is in 11th grade, while Eric is still barely out of high school, leading to an age gap of two years.
Continuity mistake: When Matt and Chester get up in the morning, Chester is in a chair with a blanket covering him up to his chin. Camera shot changes to Matt's point of view and Chester has no blanket as he speaks. Camera shot changes back to the prior viewpoint and the blanket has reappeared. (00:21:40)
Continuity mistake: Ruth is seen in a flashback. The young Ruth has a mole on the left side of her face, as does the adult Ruth. But in one shot, when she is slapped by her father, the mole appears on the right side. (00:20:00)
Continuity mistake: On the video of Ian supposedly killing Alison, we see her arm fall to the ground with her "Alison" bracelet visible. But in a later scene where Emily watches Ian put his bag in the athletics room, we cut back to the video and Alison's arm suddenly has a sleeve covering up her bracelet. When we see the video again later in the series, her bracelet is visible again.
Continuity mistake: In season 1 it's revealed that Lynette and Tom first met when working for the same company, and Tom left his girlfriend for Lynette. In season 7 it's stated that they were already dating in college, and Tom betrayed Lynette with her friend Renee.
Continuity mistake: When Jax and his crew meet up with a Hispanic gang to sell them guns and are outnumbered, they run in the station wagon. The run the station wagon through a gate and roll it, destroying the front end, but magically the station wagon's front end appears with little damage afterwards. (00:27:15)
Continuity mistake: Near the start when Mike's pulling over, the car parks literally perfectly along the side of the road. Seconds later when camera shows him stepping out it's at least 12 inches away from the curb. (00:11:00)
Continuity mistake: Charlie, Olivia's former partner and friend in the FBI shows up in this episode during the interview with Mrs. Rusk, but Charlie was killed off by one of the shapeshifters in a previous episode, and the shapeshifter that killed Charlie was himself killed off by Olivia, who in other episodes reflected back on killing him. This episode was supposedly meant to be in season 1 as ep 21 or 22. Unknown why they didn't air it then, and decided to put it in the middle of season 2 (for no apparent reason).