that was awesome. i thought that this was going to be another filler arc but it seems like it is main story line now. maybe that was a nice way to segue back to writing the real thing. anyhow it made this arc way better.
I thought it was obvious from the beginning that this was main story innocence related incident..but another level 4 is interesting...it must be something to do with the barrier..since Allen could detect the first level 4 just fine.