The Night of the Flying Pie Plate - S2-E6
Visible crew/equipment: The shadow of a boom mic is visible on a table top in the saloon.
The Wild Wild West (1965)
1 visible crew/equipment mistake in The Night of the Flying Pie Plate - chronological order
Starring: Robert Conrad, Dick Cangey, Ross Martin, Whitey Hughes
The Night of the Brain - S2-E21
Revealing mistake: Mr. Braine screams as his steam-powered chair crashes into the bandstand. If you look closely at the next shot, just before the explosion, you can see that the dummy now in the chair has its head bowed forward. It also has light brown hair, rather than Mr. Braine's silver hair. (00:47:10)
The Night Dr. Loveless Died - S3-E4
Trivia: Dr. Loveless' uncle's name, "Liebknicht", is, aside from the addition of the letter "k", German for "Loveless".