Revealing mistake: Several times during the Charles v Mike fight scene it is obvious that Charles has been replaced by a stunt double. (00:43:50)
Audio problem: At the start of Nathan Bates' angry rant, he says 'What do you mean, another van of children got through the border?' and it has obviously been dubbed as it sounds different from his following lines. My guess is that he swore originally, and it was taken out by the producers at the last minute. (00:06:05)
Audio problem: When Mike and Ham arrive at the church, their lines have been badly dubbed as Mike is still supposedly talking to Ham as he gets out and shuts the van door. (00:06:50)
Continuity mistake: When Mike radios Elias he identifies himself as 'wilderness' calling 'Shiloh'. When Elias acknowledges, he also identifies himself as 'wilderness' instead of 'Shiloh'. (00:33:20)
Revealing mistake: When Diana blasts Lydia's shuttle, there is an explosion but the craft is still visible and intact for a brief second. (00:45:20)
Audio problem: Just after Mike wishes Ham good luck, Mike shoots a guard off the roof, but he falls before the gunshot is heard. (00:44:25)
Continuity mistake: When Ham and Mike come out of the main door of the building, Mike shoots a guard standing on the roof. The guard falls off, but when the shot switches back to Mike the guard isn't seen falling to the ground. (00:43:20)
Revealing mistake: When Mr. Chiang does a roundhouse kick against Kyle Bates, he has been replaced by a stuntman. Easiest way to tell is by his hairstyle. (00:37:40)
Revealing mistake: When Diana offers the ants to the two officers, she is gripping the handle differently between the far shots and the closeup. Needless to say in the far shots the officers are not eating real ants. (00:32:50)
Continuity mistake: When Philip is first seen with the metal thing on his lens a buzzing sound is heard. Afterwards, no buzzing sound is heard. (00:17:10)
Audio problem: When Ham grabs Howie's armband and says 'our man' it's painfully obvious that the words have been dubbed by Marc Singer instead of Michael Ironside. (00:19:00)
Deliberate mistake: The shot of the cocoon gestating is taken from episode 2. This is evident because there is sand underneath it and rocks in the background, but when the tracker finds it later, there are no rocks and sand in the tunnel. (00:25:30)
Visible crew/equipment: In all of the shots of Elizabeth and Jacob facing down the highway, there is a black piece of equipment protruding from the left side of the screen. (00:42:20)
Continuity mistake: The Visitor craft that Mike and Ham capture is not the same type that is seen later entering the hangar. The first one is a small shuttle, the second is a transport, distinguishable by the windows on the side. (00:20:10)
Revealing mistake: When the building explodes at the end, the white limousine parked in front of it completely disappears instead of exploding. (00:45:20)
The Sanction - S2-E5
Continuity mistake: When Sean throws the car keys away after punching Ham, Ham's head is above the steering wheel. In the next side-on shot, his head is much lower. (00:28:20)
The Overlord - S2-E7
Revealing mistake: When the girl cuts her hand with the broken bottle, the glass never touches her hand. The blood looks really fake too.
The Sanction - S2-E5
Revealing mistake: When Kyle rescues Elizabeth from the theater, if you look closely at his face he has been replaced by a stuntman. (00:12:50)
