I just confirmed today that I will not be able to see this run of "Defiance". I checked each day that I could be in New York, and they are sold out on every one. I expect it will open again in another venue, like "Doubt" did, since they are getting great reviews, are selling out, and have already extended the showing as much as they could without interfering with their next play.
I strongly encourage people who like serious plays to go see "Doubt". It is marvelously well acted, short, intense, and well staged. I saw it shortly before Christmas and as part of a charity drive got a cast autographed playbill from it.
For an indication of what I like, I also liked "Chicago" and "Cabaret". I thought "Hairspray" was rather boring. I like some edge to my theater.