S1, E13: While in London looking for a Black Madonna, Mac is forced to go on the run from some CIA types and she soon meets a man, Gavin, who has a mark similar to one she has. Judson and Gabe go looking for her and the CIA get on their trail and claim they're trying to save Mac, who used to work for them as a freelance contractor that went undercover and was drugged to forget the guy she was sent to bring down.