Character mistake: When Beth and her mother discuss the agent's fee of 15%, Beth says it is $49.54. However the prize money was $500, the expenses were $172.30, which leaves them $327.70. 15% of $327.70 equals $49.16. (00:10:00)
Plot hole: If the Lady of the Lake walks every night to her room and kills those in her path, why didn't Flora and Miles' parents die in their room by the hands of the Lady in the Lake when they first moved in?
The Funeral - S1-E3
Deliberate mistake: Though it serves the drama and black comedy of the scene, it's highly unlikely a modern, let alone future broadcasting network would neglect the importance of delay (usually around 30 seconds) between recording and "live" broadcast. Specifically, to prevent unexpected gruesome incidents like the exploding head seen in this episode from making it to air.
Opening Act - S1-E4
Factual error: At the beginning, the screen shows that the year is 1988 in Corpus Christi, TX, then the camera pans into Selena and her sister eating tacos when their friend Jake arrives wearing an Arizona Diamondbacks shirt. The Diamondbacks did not exist in 1988. Phoenix was awarded a Major League Baseball expansion team in 1995 and the Diamondbacks made their debut in 1998, 10 years after this scene takes place. (00:00:30)
Continuity mistake: In early versions of the episode, Luz is shown wearing her Hexside school uniform before she even receives it. This mistake spoils the ending. Fortunately, it was fixed later on. (00:00:01 - 00:00:40)
Visible crew/equipment: The camera crew and camera can be seen in the far left user box during the virtual meeting on the laptop. (00:16:00)
Factual error: The communication delay for earth-moon communications is around 2.6 seconds. Yet Emma's daughter simply dials a cell phone and is connected to her Mom in space past the moon in less than that. The communication has no time lag. (00:18:45)
Remembrance - S1-E1
Character mistake: Picard and Data are playing poker at the beginning of the episode. Before the actual faces of the players are revealed, we are shown close-ups of their hands as they put down the chips for the bet. When Picard says his first line in the series it's "See", and it is literally true, because in the previous shot, Data put his 5 cards down on the table and face up. (00:00:50)
Continuity mistake: Kurt is still recovering from the beating he took in the previous episode with bad cuts on his forehead, checks and temple area. They are red and impossible to miss while he is in the police station. The cuts have miraculously disappeared in the next scene when he goes to visit Mona.
Character mistake: The FBI team responds to a murder crime scene. The victim is lying face down in the bed with blood everywhere. The team leader takes the victim's wrist with his bare ungloved hand. A trained FBI agent would never touch a murder victim without gloves - one to protect himself and two not to contaminate the crime scene. (00:10:00)
Factual error: The show, which is set in California in 1947, mentions the gas chamber, lethal injection and the electric chair as methods of execution in the state. Two murderers are sentenced to death by lethal injection and one is depicted being instead executed in the electric chair, which the governor states has been brought out of retirement for the occasion. In fact, California adopted the gas chamber as its sole method of execution in 1937 (having previously used hanging). Lethal injection was not used in the United States at all until 1982 and not adopted in California until 1993 (becoming the prime method in 1996). California has never used the electric chair.
It's Good to Be Back on the Moon - S1-E9
Factual error: The Apollo 11 flag gets knocked over by the Chinese rover...but the flag was blown over by the Eagle's takeoff thrust, witnessed by Buzz Aldrin. This was confirmed years later by the Lunar Reconnaissance Orbiter, which showed shadows of the flags planted at all six Apollo landing sites, bar Apollo 11's. The other 5 were all planted further from their landing craft precisely for that reason. It's also widely assumed that the flags on the moon would have been bleached white by decades of unfiltered sunlight, not in good condition like the one shown.
Other mistake: At the end, when the reflection of burned Lucy still shows her beautiful, Dracula's reflection shows him as he is seen; not old and ugly as in his usual mirror reflections.
Factual error: In Massachusetts, Atticus, Leti and George are attacked by the local sheriff and his deputies, who are patrolling the county roads. In Massachusetts, sheriffs run the county jails, but they do not (and did not) handle routine policing, which is the responsibility only of municipal police departments.
Continuity mistake: The background characters passing Fredwyn and Janice disappear in one frame, and then appear in the next. They also seem to randomly speed up and slow down in the background. (00:20:37)
Other mistake: Jesus leaves his home with a double barrel break-action shotgun and an ammunition belt holding extra shot-shells. In the next scene Jesus is walking in the street with the shotgun and no ammunition belt, it magically vanished. The shotgun only has a capacity for 2 shot-shells, then it needs to be reloaded, or it can be reloaded after one is only fired, that procedure is called a top-off. He fires 1 round at the mayor and two inside Elena's home which makes three. He never reloads. (00:32:50 - 00:34:40)
Facing Fear - S3-E4
Factual error: The teams are at a US Coast Guard base. Two coasties are introduced. One as a chief (correct) and one as a "Captain." He is not a Captain, he is a Lieutenant. The USCG uses naval ranks, so the person with the two bars is a Lieutenant. A Captain is three pay grades above this, and uses eagles as insignia.
Continuity mistake: An employee is asked to leave the computer lab, he actually exits it twice. (00:11:15)
Continuity mistake: When Gi-do is checking himself into the hospital, he flips up the sunglasses he is wearing. The shot then cuts to Haeng-ja whispering something to him, and we can see Gi-do's right hand raised to be level with his head. When the shot cuts back to Gi-do, his right hand is suddenly lowered. (00:31:02)
In Dreams Begin Responsibilities - S1-E1
Continuity mistake: She is on an elevator wearing her uniform. The uniform collar does not show her Chief of Police stars on it but when she walks off the elevator down the hall into her office less than 10 seconds later, the stars reappear on her collar.