Deliberate mistake: When Batman and Robin get free from the train tracks in the nick of time, the shot of the couple on the passing train is flipped; note things are backwards. (00:04:30)
Visible crew/equipment: At the end Harriet surprises Bruce and Dick with a rehabilitated criminal, and when Blaze walks in we can see the shadow of the moving boom mic on the left side of the screen. (00:23:05)
Continuity mistake: When False Face escapes from the bank he has Blaze with him in the Town Panel truck, and she's handcuffed to the overhead pipe. Blaze is wearing a neutral color nail polish, but in the closeups of her cuffed hand her nail polish is salmon colored. (00:14:30)
Other mistake: While Batman and Robin are pursuing False Face, they stop the Batmobile beside a fence (across from "Bioscope"), and a sign that states "No Trespassing, Desilu Studios" (the show's studio location) is mounted on that fence. (00:15:00)
Answer: There were three well-known actors who played Mr. Freeze, each one a different height, weight, and physique. As these were notable guest stars, the costume designers would adapt the costume to best fit each actor who likely would want to avoid comparisons to the other Mr. Freezes, incorporate their preferences, as well as refresh the look, rework whatever didn't work in previous versions, and so on.
raywest ★