The serial killer's counterpart is John a psychology professor with some skeletons in the closet. Due to people being idiots, he soon cops on to the profiler, profiled deal. The team are idiots some more and John runs off (after finally seeing the huge amber mountain) to find alt John and fix him. Alt John doesn't want fixing. He needs a wash though.
We get info on how Olivia's past was changed and how John may be changed (will they bring him back later in the season?). Walter annoys some more and poor Joshua Jackson is ignored some more. This was good.
"He can never know that you exist."