1. When the unexpected bad happens.

2. The small probability of something going in the wrong way.

'N.B: the verb "goes" can be in any form up to the time tense when it's used. e.g: went, gone, go, (be) going, (has) been going, (will, must,..).etc'
- "Hello Mr. officer, what's your duty here?"
"Everything seems fine so far, I'm here just in case shit goes down"
- Cops are never around when shit goes down!
- "Take this gun buddy, just in case shit went down"
- "You never know son, because when shit goes down, it'll be too late"
by Mr porter tha elicist January 15, 2010
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