While the team investigates the theft of a computer virus, Callen and Sam consider their future at the agency, Kensi and Deeks discuss having children, and Eric and Nell analyze the impact of Eric's undercover assignment on their relationship. Also, the team tracks Mara a crooked upscale banker.

After a rise in deaths caused by black market opioid use, the NCIS team links the street drug to funding for terrorist activities.