A tactical team was ambushed while trying to take down a cartel with terrorist connections. The mission was highly classified which brought suspicion on the military contractors that trained the team. In order to track down the leak, the NCIS team goes undercover to train with the contractors. During the training, one of the contractors is killed and heightens the suspicions about what was going on. Granger hid that he was friendly with the contractor's leader, David Inman. 

They undercover that Inman is building a new multi-million dollar facility paid for in cash. They realize he is on the take. Nell was left to investigate the murder site and then kidnapped by Inman. The team goes in and kills Inman and his team to save Nell.