Ep 23. Greatest Hits

Charlie learns that one of his former math students is part of a group that has been committing credit card fraud, but he has a hard time believing it. When Don and the team start investigating, they discover a connection to a notorious hacker, but their efforts to track him down are thwarted at every turn. Meanwhile, David and Colby go undercover to try and catch the fraudsters in the act, and Amita makes a decision about her future. As the investigation heats up, Charlie realizes that he may have put his former student in danger and must do everything in his power to protect her. With each new piece of information that comes to light, the team gets closer to unraveling the mystery behind the greatest hits of a cybercriminal's life.