Assassin (S02E05)

Along with David Sinclair and new FBI Agent Colby Granger, Don discovers a secret code during a raid and enlists Charlie's help to crack it. Using an elaborate game theory model called "hide and seek," Charlie discovers that it is a plan for the assassination of a Columbian exile living in Los Angeles. Charlie and Megan combine their expertise and work closely together to try to prevent the murder from taking place. (iTunes)