[ChipLeader]

1.) How did villian double so early? Judging by stacks he won an all in on one of the first couple hands and this only a few hands into it. Check history, see how he played whatever hand he doubled with and check for tendencies that indicate strength or weakness; ie if he lead in with a set last time, now is an easy time to fold, as oppose to if he lead in with nothing and caught, c/r, etc.

2.) Unless you get some nice read from #1, and you wont get THAT good a read often, follllld flop. You should now be getting an idea for the type of player villian is, nothing concrete but hes been active so far- try to decipher what hes playin.

3.) Turn is only a call if youre sure he flopped strong and think he'll pay the straight, and the A is likely good. The only other benefit of this call is that he may just check/call river with a good but not great hand, meaning you can check behind and see his hand (very valuable to know what type of hand he leads into the PF raiser with.)

As played, you cant fold, if he has JK thats too bad. Obv he could have a much wider range since you gave us no reads on him- could be a flopped set, could be an overplayed 2 pair, could be a stone cold bluff thinking that river was a scarecard completing the 4 straight, or could be another J. Call, pray, dont get so invested in this pot next time without a GOOD reason.