Revealing mistake: The captain's arm that was removed can be seen wrapped in a green screen editing sleeve when he is in the hospital. (00:39:55)
Continuity mistake: Miguel kicks and breaks a staircase railing during the school brawl. For a second it cuts to Robby. When it cuts back to Miguel, the railing is fixed.
Character mistake: The firefighters state that the acronym for CPR is ABC for Airway, Breathing, Circulation. This is very outdated as in 2010 the American Heart Association changed the recommendation to CAB for Compressions, Airway, Breathing following evidence that compressions first in CPR saves more lives.
Continuity mistake: Rick pulls up in a car to the right side of a helicopter, gets out, and gets in the helicopter. When the helicopter is shown taking off, there is no car next to it. (00:38:20)
Episode #1.1 - S1-E1
Factual error: The American flag shown waving outside the White House is the current present-day flag with 50 stars. From 1896 to 1908, (the time period that this show is set in) the US flag only had 45 stars as Oklahoma, New Mexico, Nebraska, Alaska and Hawaii were not recognised as states in that time period. The flag did not have 50 stars until 1960. (00:04:30)
Continuity mistake: As the US Embassy in Caracas, Venezuela is being evacuated, the ambassador steps into a Black Hawk helicopter with markings 33 and 3016. After her Black Hawk arrives at the Aeropuerto Francisco de Miranda Airport in Caracas, it has markings 60 and 2065. (00:25:48 - 00:29:20)
Factual error: When Starfire gets out of the totalled car, there is a road sign visible. It is a settlement exit sign, denoting the exit of Königsstetten and Zeiselmauer as next settlement ahead. Obviously the makers tried to be extra thorough nailing down their "outside Vienna" location. They started OK - both Königsstetten and Zeiselmauer actually ARE outside Vienna - but then they completely botched it: Not only did they use a German black-on-yellow "StVO Zeichen 331" instead of the Austrian "StVO Hinweiszeichen 17b" which has black writing on a white base with a blue rim and doesn't list the next settlement, but they also put 852km as the distance to the next settlement, which is more than the length of Austria west to east. The real distance is 3.8km.
Black Blood - S1-E1
Other mistake: All the Greek name variants are used over the Latin ones - including even "Odysseus" over the more familiar "Ulysses" (who is the same person). However when the story of Actaeon comes up, it's suddenly the goddess "Diana" that he saw. But all the gods have their Greek names, so that should be "Artemis." (As indeed is used in episode 2). (00:39:35)
The Book of Occupation: Chapter Five: Requiem for Tavon - S3-E5
Visible crew/equipment: Right before Anissa and Tavon are attacked by Khalil, the shadow of a camera can be seen on the ground in the bottom right corner of the screen as they approach the path.
Other mistake: The shopkeeper hands Danny a Beretta 92fs/M9 handgun with a detached suppressor. To mount a suppressor to the muzzle end of the handgun the barrel needs to be threaded, and this one isn't. Sometimes barrels are threaded and when no suppressor is attached they are protected by a thread barrel cap to protect the threads from dings and bumps. There is no thread cap here either. (00:22:35)
You're Mine - S2-E8
Continuity mistake: After Eve kills Raymond, Villanelle tells her to take her shirt off. In a shot from behind, Villanelle puts her hand around Eve's back. Then it cuts to a shot beside them both, and both hands are in front of Eve.
Revealing mistake: When Mitsuhashi and Ito meet on the first day of school, the clock in the classroom never advances from the 8:20 position despite the scene taking place in a span longer than one minute. (00:04:45 - 00:06:08)