A fork of Rural Dictionary
Warren: "You know I saw Jeff at Steve's Place the other night." Rick: "I can't stand that cat, man. Fred: "Word, man. That cat is always trying to play us like fools."
Basically, this is when emotions break loose and people get hurt. A literal meaning would be that shit gets on everybody due to the intrinsic nature of the fan.
"I found out my brother was sleeping with my wife, and that's when shit hit the fan."