[dave44]

Posting blind.

I like the flop play. Unknown is very likely raising any pair on this board. 3-betting lets you knock out the preflop raiser when he has overcards to clear up some outs for yourself and gives you a chance to knock the unknown off his pair if a scare card hits on the turn. If the preflop raiser doesn't fold, at least you're getting about even money on your raise since you have the flush draw.

Heads up on the turn, I wouldn't bet just any card. Unknown most likely has a pair and I doubt he folds it to a complete blank. I would bet any ace, king, queen, jack, and eight. I'd say a ten is borderline. Anything else, I'd rather just check-call.