Continuity mistake: When Miss Porter enters the office, the coffee mug on Lom's desk jumps from the blotter onto the wood surface between shots, even though no one touches it. It also reverses its orientation: the handle switches from pointing left to pointing right.
Continuity mistake: Harker confiscates firearms from five Devil's Hole members who are playing poker in the saloon. The sixth member is down in the tunnel, and didn't turn over his gun. Yet when the outlaws go to collect their weapons, six are given back their side-arms.
00:49:00 - 00:55:50Jean G
Factual error: Kyle strikes a match on the wooden floor to light the dynamite's fuse. In the early 1880s (the era in which this series is set), a portable flint-and-tinder kit was the common method of sparking a light. While "strike anywhere" matches had been invented by this time and were quite the rage in Europe (despite an alarming tendency to explode due to the volatile chemicals used), they were an unknown commodity on the American frontier until well after the turn of the century.
Continuity mistake: When Harker rouses a sleepy Heyes and drags him to the saloon, Heyes' hair is falling over his forehead. The shot cuts, and his hair is combed back. Then he steps through the curtain to talk to Wheat, and the hair is over his forehead again.
00:46:50 - 00:47:30Jean G
Continuity mistake: Deputy Harker keeps checking his pocket watch while making his rounds. The first two times he looks at it, the watch face has Roman numerals. On his third check, it has regular numbers instead. The fourth time, the Roman numerals are back again.
01:05:15 - 01:06:45Jean G
Continuity mistake: In the saloon, Heyes and Curry are standing at the bar about four feet apart. After the deputy sheriff kicks the orchestron (a 19th C. jukebox), the camera angle reverses - and Heyes and Curry are suddenly shoulder-to-shoulder at the bar.