Factual error: The camera starts out-of-focus looking down a crowded sidewalk full of background actors in period clothes and hairstyles (1973). As the camera racks into focus, Sam is walking toward the camera with many awnings visible in the background - a large blue one reads "24 Hr ATM". Though versions were invented prior to 1973, they didn't come into wide usage until the mid-to-late-80's and certainly weren't available in East Village bodegas at the time of this episode.
Plot hole: The car was tracked down by finding the original car key on Jimmy's body. If he had stolen the car from the original owner, how did he come to have the original car key?
Visible crew/equipment: Dutch and Claudette are watching an interrogation video of the Margos with Armin Chorekian. Just before the scene changes, the boom mic bobs down into the shot above Armins' head for a split second. (00:14:40)
Episode #1.1 - S1-E1
Factual error: This is set in 1933. When the killer comes back to his lodgings in episode 1, Lily on the stairs is humming "Somewhere over the rainbow", which was written for The Wizard of Oz in 1939. She also happens to wear bright red shoes, which feels like yet another Wizard of Oz reference. Interesting enough, the subtitles say that she is humming a different song, "Night and day" which she openly sings throughout the series and was already a hit in 1932. (00:44:10)
Visible crew/equipment: In the rec hall, when Kensi feigns sickness while posing as a cadet the gunman jumps off the stage, and as Kensi bends over the small rectangular bulge of her mic pack can be seen at her back. (00:30:25)
Revealing mistake: At the end it is not Helen against the filing cabinet - the face is different. Obviously a body double.
Continuity mistake: When Dr Jeremy Kates rushes into the ER when Frank crashes, he doesn't have surgical gloves, a moment later you see him draining fluid from his heart and he is wearing gray gloves.
Plot hole: "Showdown": Darien's lost hat and jacket reappear without explanation after Kane finds him wandering in the desert. Also unexplained is how Kane conveniently happens to be leading an extra, unnecessary horse - unnecessary, at least, until he stumbles across the stranded Darien. (00:15:00)
Continuity mistake: In episode 3, "How Billy Got His Groove Back", in the scene where Mick is meeting with Eduardo on the overpass Mick's sunglasses keep switching between being up on his nose to down on the tip of his nose to being off his face and back on again.
Continuity mistake: When Bug speaks with the beautiful widow the second time, about performing a noninvasive autopsy on her husband, her long hair continually changes position in the shots that face her.
Factual error: There is no physical way that Steve Austin could perform most of his superhuman feats of strength in the ABC television series, due to the fact that they simply replaced his arm and legs, but didn't rebuild or reinforce the rest of his skeleton and muscles to handle the physical loads. Interestingly, author Martin Caidin (creator of Steve Austin in his novel, "Cyborg") actually did describe an incredibly complex whole-body rebuild that included vertebral reinforcement and ribcage and pelvis replacement, which was far more scientifically-accurate than the subsequent ABC television interpretation. ABC only accepted the series on the condition that it was less technical for their audience.
Continuity mistake: In season 4 of Prison Break, Mike Scofield's tombstone date of death shows 11-4-2005 but in this the date is 11-4-2010.
Factual error: Superintendent Kane wears the insignia and uniform only worn by the Commissioner of the Metropolitan Police, not only six ranks above the rank he is supposed to be, but in an entirely different police force.
Continuity mistake: Ava spills Coke on her blouse and creates a big circular stain. As she walks to the bathroom, the stain becomes a long narrow one. When she is leaving the pizza place, the stain is still narrow, but much shorter. (00:21:00 - 00:22:00)
Revealing mistake: At one point when Alan's phone rings (Nokia 8310) he answers it and talks to the caller yet it's obvious he isn't talking to anyone. He blatantly presses the red/cancel button to answer the call. The image hadn't been reversed though, because he pressed the exact same button to end the call.
Visible crew/equipment: Diamond parks outside the apartment house, and when he opens the car door, it mirrors several stage lights and reflectors.
Visible crew/equipment: In "Don't Pet the Teacher", when Jeffrey Stone talks to Albert the janitor, a boom mic briefly dips into the shot over Jeffrey's head. (00:06:10)
Continuity mistake: When Sheila Carlisle has hanged the dead head up on the wall of Eugene's office, they are all looking at it and the eyes are looking straight in to the room. Later in the episode, the eyes are looking more to the right.
Kingdom Come - S1-E6
Other mistake: At the start of chapter 12 in the episode "Kingdom Come," Frank returns home via taxi. In front of his house in Seattle, WA, there is a blonde woman walking a Rottweiler dog. This same blonde and Rottweiler can be seen walking by the crime scene in San Francisco in the "Gehenna" episode.
Continuity mistake: When Shirley walks through the door you can see over Alan's shoulder that he's reading the comics in the daily paper. As they talk the paper changes to the business section.