Following an explosion at a fish market, the NCIS: LA team partners with an undercover DEA agent to determine if the incident is an act of terrorism or a botched drug smuggling deal. Meanwhile, in Afghanistan, Granger and Kensi investigate a helicopter crash that could be tied to their ongoing search for the infamous white ghost.

The NCIS: LA team is called in to determine if the computer system that controls Russian missiles is at risk after Eric overhears his friend, a computer systems expert, being attacked during online game play. Meanwhile, Kensi is shocked when a familiar face from her past shows up in Afghanistan.