In order to get intel on a matter of national security, Kensi must come face-to-face with a sociopath who has been obsessed with her since she put him in jail years ago. Also, though Deeks is desperate to keep Kensi safe, he is forced to leave NCIS.

The NCIS team's murder investigation of a man who sold military information leads to the abduction of a doctor whose cutting edge neurotechnology could be developed into advanced weaponry. Also, team members are interviewed by FLETC to see if Deeks would make a good NCIS agent, and Callen tries to have an important talk with Arkady.