We open CO with 200bb's...
Get 3bt from BB, covers. Pretty normal sizing - 11bb's.
We have

- fold pre seems too tight when we have 200bb's, we call.
FLOP

He cbet just over half pot, we just call....
I figure if he has Ax he will continue, if he is bluffing I have to let him continue - its a 3bp so we should be able to bet big enough on turn if checked to or raise river if needed to get it all in.
TURN 
He now bets $25 into $21..... this is a pretty unusual line from regulars, potentially a 'scary bet - I'm going to shove river bluff' or could just be QQ, AA, AQ ....?
I don't really see any other option than to call.
RIVER 
Takes a few seconds then shoves for the remainder, covers us......
What now?