if a plan, etc. blows up in your face, it goes wrong in a way that causes you damage, embarrassment, etc.
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if a plan, etc. blows up in your face, it goes wrong in a way that causes you damage, embarrassment, etc.
If you tell everyone about the stock deal, it will blow up in your face.
And now it's going to blow up in your face.
Definitions from the Oxford Advanced Learner's Dictionary, 9th edition