Sam and Kilbride clash when a case involving an arms dealer responsible for the slaughter of ATF agents leads them to a well-connected General and friend of Kilbride, accused of supplying militia groups with guns. Also, Kensi and Fatima go undercover at a rehab facility to question the arms dealer's girlfriend.

When an NCIS mission to protect a compromised undercover agent goes completely sideways, the agents are individually interrogated to find out what really happened. Also, Kilbride must make a difficult decision.