The Night of the Deadly Bed - S1-E2
Revealing mistake: Electrical sparks between the wheels and track rails are visible under the coal tender of West's train as it rolls, showing the train is an electric model.
The Night of the Firebrand - S3-E2
Revealing mistake: Dust is kicked up and tire tracks from the camera vehicles filming the chase scenes are obvious.
The Night of the Bubbling Death - S3-E1
Revealing mistake: The arms of the unconscious bad guy West drags by the feet should be dragging above the shoulders, not almost parallel to his body.
The Night of the Puppeteer - S1-E21
Revealing mistake: Zachariah Skull's bald head has a problem. The latex skull-cap used to cover the actor's hair keeps bubbling and wrinkling as he speaks. (00:43:00)
Revealing mistake: "Night of the Running Death": During West and Gordon's poker game at the end, Gordon tilts the table by at least 30 degrees - and none of the poker chips, cards or cash moves an inch. Apparently, everything was glued down. (00:44:30)
The Night of the Flying Pie Plate - S2-E6
Revealing mistake: After they're carried inside and placed in chairs, one of the "unconscious" women moves her arm into a more comfortable position. (00:33:00)