Ever since this thread started I've had some obscure thought gnawing at me and it may have just come to me (note I said "may"). I want to say that in several Charlie Chan and Sherlock Holmes films there were disguises that utilized some latex. Maybe not as all encompassing as those portrayed in scenes we've talked about, but it seems like there were fairly elaborate masks used in those two film series. Charlie Chan at Treasure Island had Cesar Romero wearing an interesting mask of sorts. Then again, these examples I'm thinking of aren't necessarily full latex masks. I know one thing though: I'm going to keep an eye out for any examples from this point forward when I'm watching anything done prior to the mid-60s.

Gary "WWW just wasn't the same when Martin was out" O.

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"Do not challenge supernatural unless armed with sword of truth" - Charlie Chan at Treasure Island