Revealing mistake: As the team is headed to Warren's hometown the show shows a clip of zombies in the field but it's the same 12 people (exact same outfits too) used in 11 different places in the exact same shot.
Revealing mistake: At the end of the episode when they show Citizen Z, the computer on his left has data or some kind of code running down the screen. Right after he puts his glasses on, the pause button appears mistakenly on the screen, revealing that it's not legitimately a program running, but just a video the effects team setup.
Revealing mistake: The lady that is with the other two guys that kidnapped Murphy decides to remove her magazine from her pistol. It's an airsoft pistol. The magazine has a front feeding area for 6mm BBs, and looks weird in general. She also has no ammo, as you can see the entirety of the internal spring - not bullets. And the magazine is weird too.
Die Zombie Die... Again - S1-E10
Revealing mistake: When Murphy gets back to the group after having walked about 10 miles with Amelia following who is now a walking Z, why doesn't she run past Murphy to the others?