Surf's Up! Joker's Under! - S3-E10
Visible crew/equipment: After Batman and Robin head out to Joker's hideout, when it cuts to Joker upon his success at stealing all of Skip's talent and vigor, just as Joker says, "You know what this means boys, the surfing championship," we can see the shadow of the boom mic moving at the far right side of the screen. (00:09:50)
Surf's Up! Joker's Under! - S3-E10
Visible crew/equipment: After Batman wins the competition, when Hot Dog is finally released from the trash can Joker rushes over to claim it was just a little joke, and the microphone pops up into view at the bottom of the screen. (00:21:10)
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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