Continuity mistake: When Jack is using the mustard to find Martha, Vincent ducks behind the counter. The shot changes to show just Vincent and he is shown ducking down again.
Best in Faux - S3-E3
Continuity mistake: Henry is showing Zoe how to melt a penny, but in the next shot the penny is not melted.
Best in Faux - S3-E3
Continuity mistake: When Dr. Mendel picks up the beaker with the blue liquid it is almost full, but when he goes to pour it out the beaker is almost empty.
Continuity mistake: When Henry is carving Dr. Nathan Stark in the wall, we see him carve the H and the wall says DR. NATH. As Jack is walking in an A appears after the H.
Other mistake: Captain Eureka losing his finger makes absolutely no sense. He doesn't cry out in pain, there's no blood, and where the finger ended up is completely illogical. The finger didn't just sever on its own; it's shown that severing only occurs when passing through objects. Captain Eureka goes through a wall that is a good fifteen feet away from where the finger is discovered, and it is implausible to think it could have rolled there on its own.
Plot hole: When talking about rescuing the kids, Carter mentions them in the plural. But so far, all they have to go on was Zoe's birthday, so they wouldn't have known that anybody else was there, and Thorne also had not said anything about Zane.
Factual error: Zane used ULF (Ultra Low Frequency) to communicate with Henry and notes he can "only send numbers." This is a reference to extremely low bandwidth of maximum 300 Hz transmission. However, later Henry magically creates an upgrade that allows voice communication - not possible with ULF. Also, no way Sheriff's old radio would pick up ULF band communications in the first place.
Continuity mistake: When Jack and Lexi are in the jeep talking a car can be seen in the mirror, but when they pull over no car passes them.
Continuity mistake: When Captain Eureka puts out the fire at the pumping station, Jack's Jeep somehow gets on fire, but we are able to see where the fire went, and it didn't come anywhere near the road or the Jeep.
What Goes Around, Comes Around - S3-E18
Plot hole: Tess sends Jack an airline ticket to visit her in Australia. The ticket reads 'From: Eureka, Oregon, To: Sydney Australia.' Seems odd that a commercial carrier would have a terminal in the most secret town in America. Eureka is a town created by the US government for its top scientists to experiment with new technologies. It is made nearly invisible from the outside by giant holograms. Very few non-residents even know of its existence.
Suggested correction: There's nothing to suggest Eureka has a terminal open to the public or other commercial airlines. In fact, the airline is named CircumGlobal which is probably not a coincidence that it shares part of its name with Global Dynamics. It could be a private airline only for Eureka staff and citizens.
Factual error: At the dance in 1947, a US flag with 50 stars is visible.
Continuity mistake: At the beginning of the scene where Dr. Grant gives Jack the crank for the satellite dish, Henry turns his hat around so it is backwards, later on in the scene it is now facing forward, then is backward again, then at the end of the scene he is seen facing it forward.
A New World - S4-E2
Continuity mistake: At the end of the previous episode, when Jack comes home to find Tess there, Tess says "I thought you'd never get here" and then asks if he wants a drink and goes to the kitchen. In the beginning of this episode (which is suppose to be the same scene) she says "I thought you'd never get home" and Jack replies "you're not in Australia" and then Tess asks S.A.R.A.H. to make him lunch.
All the Rage - S4-E3
Continuity mistake: When Fargo and Jo are going to the section three lab, a scientist holding a beaker runs into them. He spills the liquid and bends down to clean it up. The amount on the floor changes from shot to shot.
All the Rage - S4-E3
Revealing mistake: In the very first shot, we see the sky, and you can tell it's a digital image imposed on a green screen instead of a shot of the actual sky.
Continuity mistake: When Jo is waking up from her surgery, both hands are on her stomach. The shot changes, her right hand is on her chest and her left hand is off her stomach.
Continuity mistake: At the end of the previous episode, when Carter tells Grant not to plan the wedding just yet, Carter leaves Cafe Diem and Grant says "May the best man win," as an aside. In this episode, the replay shows Grant saying this while Carter is still in the cafe, just in front of him.
Revealing mistake: When Jo comes riding in with the horses, you can tell that it's a stuntwoman in the far shot.
Continuity mistake: When Jo comes up to see her new house burned down, there's a lot of sunlight. When Zane passes by, the shot changes and nearly all the light is gone, as if it were dusk.
Continuity mistake: In the scene with Dr Lee, the old man, at one point, he waves with his left hand, then the angle changes and he's waving with his right hand. (00:20:35)
