(the) shit hits the fan
US /ðə ʃɪt hɪts ðə fæn/
UK /ðə ʃɪt hɪts ðə fæn/

1.
事情變得一團糟, 爆發大麻煩
a situation when a problem or crisis becomes public and causes a lot of trouble or anger
:
•
When the news of the scandal broke, the shit hit the fan.
當醜聞曝光時,事情就變得一團糟。
•
He knew that if his boss found out, the shit would hit the fan.
他知道如果老闆發現了,事情就會變得一團糟。