Starring: Robert Conrad, Dick Cangey, Ross Martin, Whitey Hughes
The Night of the Tartar - S2-E19
Other mistake: As the coach is entering the courtyard, Count Sazanov and Anastasia are standing side-by-side. In the space between them, one can see by the gate's entrance, a car driving from right to left. (00:22:15)
The Night of the Bubbling Death - S3-E1
Revealing mistake: As West drags the body of a bad guy out of the scene, the supposedly unconscious man is holding his head up so as not to have his head dragged through the dirt. A truly unconscious person's head would flop back on to the ground.
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".