Today, the New York Times online edition reviews a documentary film. The review contains the following sentence:
The filmmakers don’t villainize anyone, though a few participants come awfully close to twirling waxed mustaches, like an American manager who jokes to a Chinese colleague that it would be a good idea to duct-tape the mouths of talky American workers.
It’s clearly nothing positive, but I have never heard of it, cannot deduce the exact meaning from context and could not find anything online, partly because most hits concern physical mustaches.
In the sense of ‘twirling waxed mustaches’: Dastardly Whiplash
An oddly specific kind of character, the Dastardly Whiplash is a
cartoonish villain taken from the silent film tradition [1891-1920]. Usually a Man of Wealth and
Taste, in Great Britain (cough Evil Brit cough), he was generally a
Bad Baronet; in the U.S., he was often an Evil Banker who held the
mortgage on the heroine’s farm. Physically, he’s slightly hunched with
an exaggerated nose and chin, a curling black moustache (all the
better to twirl at you, my dear)
At home, too, beards and mustaches reflected a kind of masculinity
that was falling out of favor. In 1920, Alma Whitaker, a Los Angeles
Times columnist, complained that “tricky little mustaches” found on
men returning from World War I
I appears from vaudeville to the the ‘talkies’ to the dashing soldiers of WWI returning, the twisting part came to connote ‘evil design’. My sense would place this figurative usage in AmE at the turn of the 20th C.