The Rex Montana Story - S1-E35
Revealing mistake: When Flint follows the Indians, there's a strong wind blowing. But the two puffy clouds in the backdrop sky never move.
Revealing mistake: When Jan Clayton picks up the baby to go outside and torch the wagon, she swings the baby around carelessly, revealing the shiny (and unsettling) head of an old prop baby doll. (00:37:15)
The Rex Montana Story - S1-E35
Revealing mistake: When Rex interrupts the poker game, the camera pulls in for a close-up of the lantern - so close that we can see it's illuminated by a big round light bulb.
The Mary Halstead Story - S1-E10
Revealing mistake: Mary dies at the end, but while Adams comforts Tom, it's apparent that her corpse is still breathing.