Better Luck Next Time (2) - S1-E20
Continuity mistake: While Batman is increasing his communicator's audio modulation so as to incapacitate the tiger, Batman is wearing Bat Ear Plugs to protect his hearing. As Batman turns his head in the closeup, we're able to see that the Bat Ear Plug has vanished from his right ear, then it reappears in its proper place. (00:04:55)
Answer: It's wasn't unusual for multiple actors to play one character on this show. The villains on the TV Batman were played by guest stars, not regular cast members. George Sanders, Otto Preminger, and Eli Wallach played the part at various times. They may simply have only wanted to play the part once or twice, or they were later tied up with other projects, making it necessary to cast someone else. Other characters, like Catwoman, were also played by more than one actress.
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