Sherlock

A noun turned adjective depicting someone who lacks common sense or someone who mentions the "obvious".
A substitute for "Captain Obvious"
A sarcastic way of calling someone a genius.

Person: Dude, she's a girl!
You: Yeah, no shit Sherlock

awry

For shit to hit the fan.

I thought it was being a brilliant idea to study just before the exam, that way I would retain most information, but I was wrong, and the examination went awry and out of my hands.