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What I read is that Saul is the one who has been turned. They say that he greeted Brodie's guard with that odd affectionate greeting. Remember? And the he is the one who gave that guy the razor blade, not Brodie. Saul was turned when he was held captive a few years ago. Remember Carrie talking about that in this last episode? Saul also okayed the bugging of Brodie's house, since he knew they would get nothing. Saul also authorized them to enter the house near the airport, because he has already warned the couple to get out. He's allowing Carrie to focus on Brodie, because it keeps her busy and off his case