[Pokey]

Now you fold.

Your preflop four-bet shrinks his range severely -- you can put him on AA, KK, QQ, and AK. That's about it. Of these hands, you're ahead of AK, and that doesn't check-raise all-in on this flop. You're done; if he's got the huevos to bluff-raise all-in on this flop, he deserves to win.

Your mistake was the three-bet preflop: you set yourself up for heartache. You give away your hand and simultaneously leave enough money behind that you'll be miserable putting it all in the middle.

Better would be to smooth-call the three-bet. Then you can either call down flop-turn-river or put in a good raise if you catch a K. If an ace comes and villain two-barrels you can fold the turn. Otherwise, call on down -- you win the most when you're ahead and you lose the least when you're behind. Villain is aggro enough that you he'll value-bet himself to death against your KK.

If you were much shorter, a four-bet all-in would be a good choice. I'd advocate that with $50 stacks or less, since you get called by hands like AK and QQ. Given how deep you are, a four-bet all-in preflop is ridiculous, and if you're not getting it ALL in preflop you shouldn't be four-betting.

Oh, and as played I check behind on the flop. Why open yourself up to a bet you can't answer? You're afraid of no turn cards other than an ace, and that's as likely to scare villain than it is to harm you. You keep the pot smaller and you induce turn bluffs that are going to be more +EV to call. Your flop bet builds a gigantic pot, and your hand can't support it.

Besides, if you bet the flop and he check-raises, then what would you do? Man, that would suck, huh?