Thank you @Alive99. To answer your questions, he criticized a tactic I employed which is in fact, working out well on a client website, he unfairly compared me to a far more junior staff member, he criticized more of my work then picked out one single mistake I had made since I had come back on board to nitpick at me and accuse me of being unprepared for a client meeting, when I had been fully prepared. He said this because I fumbled to answer the client's question when they asked me a question. I felt he was being demeaning and rude by comparing me to someone more junior than myself who did far more basic level tasks than I am doing, that it was unfair and rude to criticize my work, not once but twice, and unfair and rude of him to nitckpick over one thing done wrong when I've done everything else correctly and very well to date.

I had one interview already, and I am having another one with a different company tomorrow. I am definitely leaving, I decided. I will not put up with this kind of demeaning treatment from anyone.

And thank you @poshgirl. Yes, there could be several different reasons why he was this way towards me, but I will never get to the bottom of it. Perhaps he does feel threatened by me, which is very possible since I gave a lot of ideas when I first came back on board on how to improve the team. It almost doesn't matter why he did what he did - the fact of the matter is it was completely inappropriate and wrong of him to do. I chalk it up to him showing me his true colors on that day and for me to steer clear of him.