Inglês: somebody's mask slips, slipped, will slip
If someone's mask slips, they do something which shows people their real personality, when they have been pretending to be a different, usually nicer, type of person. - Thefreedictionary
Exemplos:
- Unfortunately, the mask slips when Leanne tells him that not only will she not be coming with him to the play, she's resigning, causing self-pitying Peter to hit the bottle.
- His mask had suddenly slipped, and she saw him as the angry and cruel man that he really was.
- The day David Cameron's mask slipped. Calling Ed Balls 'the most annoying person in modern politics' revealed David Cameron's true toffish colours.
- I suspect that at some stage the mask will slip and the honed, festering resentment will be horribly evident.

