a 'masked' ball [=a formal party for dancing at which people wear masks]
She 'masked' [='hid'] her anger with a smile.
The bank was held up by 'masked' robbers.
(..) - Oh, I can see that. - Of course you can. I'm not questioning your powers of observation. I'm merely remarking upon the paradox of asking a masked man who he is. - Right. - But on this most auspicious of nights... ...permit me then, in lieu of the more commonplace sobriquet... (..)2005 V for Vendetta