When things get chaotic or uncontrolable, shit has hit the fan.
3,000 people were waiting for the movie 7 hours before it opened. When it was announced that the movie would not be showing, 50 chimps on motorcycles parachuted down from the sky. The monkeys pulled out assorted automatic assault weapons and then the shit hit the fan.
1. When the critical moment occurs, usually involves the culmination of some sort of crisis or scandal.
2. When shit is literally slung into a fan. (See the movie Airplane.)
When your wife finds out, the shit's gonna hit the fan.
The point at which "the shit hits the fan" is the point at which an already unstable situation devolves into utter chaos, often in spite of--or even due to--a higher authority's attempt to control it.
"But what happens if the cops try to suppress the protest?"
"Well, then, the shit hits the fan."
"A full-scale riot?"
When something you've been trying to cover up goes public.
The shit's hit the fan! They found the bug in the DA's office!
when something blows up, goes big in the news, etc..
people talking shit, but when the shit hits the fan, everything im not, made me everything i am
You are worried about your current situation? Wait 'til the shit hits the fan!
Its when the real serious moment comes
Eminem: So what you gonna do when shit hits the fan, are you gonna stand and fight like a man, will you be as hard as you say you are, or your gonna run and ditch your body guard.