Dr. Shimel wrote:The indelicate question of Eartha's color and the lack of a comparable stagehand/extra to fill her place might also explain the re-emergence of "Julie" as Catwoman. I've also noted before that the romantic tension between Batman and Catwoman stopped once Eartha took over, since I don't imagine Dozier wanted to deal with the inevitable blowback from even hinting at an interracial relationship.
Oh, Eartha would have had a stand-in, for lighting purposes - too expensive to make the guest star stand around, even in the 60s, and probably a dark-skinned stuntwoman had her scripts required stunts, and if one was available. There may have been very few female/black stuntwomen at the time; didn't a small male jockey/stunt guy play Batgirl in the horse race episode? (Many bit-part actors also were registered as stunt performers - sometimes in the 60s they did "extra" work for one studio under one name and stunts for a different studio under a different name). But "stagehand" would never be the correct term for such a job.
(There was a controversial union
faux pas in the 80s with "Star Trek II: The Wrath of Khan", when a white stuntman was put into blackface to double for Paul Winfield, when the director wanted an impromptu roll down a sand dune. Which was never used in the film. I think in the 60s, it may have been quite common to put white stunt people into matching makeups for actors, but the rules were more lax.)
My point being, it was the penultimate episode, all the regular villain stand-ins/stunt guys were getting one last play in the iconic arch villain costumes, so Marilyn Watson got the gig.
Would Eartha have returned for a Season Four? Anyone's guess. She seemed to be having fun in Season Three. (And yes, they used the character more as a foil for Batgirl, rather than romance for Batman.) But as a cabaret singer and actress, she may have been just as busy as Julie Newmar and Lee Meriwether.