CyberCom investigates a terrorist suicide bombing at a U.S. Marine base and learns a new, chemically undetectable bomb material is being consumed. Meanwhile, Riley is forced to make a drastic decision when she finds Gabriel unable to complete a task.

Gabriel and Riley pose as Secret Service agents in Syria in order to rescue two American journalists being held hostage. While there, Riley must work with her former boyfriend, and the truth behind their past is revealed.