While Sam investigates the murder of an Iranian exile working to overthrow the current regime, he must also try to save Agent Roundtree, a new agent who's having an unexpectedly adventurous first day on the job, when he accidently triggers a bomb. Also, Nell makes a decision about her future.

NCIS helps a former NCIS tech operator search for her missing ex-partner, when they fear he might be working with the gun runners they failed to take down years ago. Also, Callen reveals to Sam that he's about to put down roots with Anna, and Deeks reels when his bar gets a negative review.