When two Naval officers who worked at the Naval Security Group's cryptography unit are shot dead with a third surviving, Harm investigates and is shocked when he learns that one of the victims is an old friend of his with things becoming intense when Harm learns that his friend was suspected of passing state secrets and highly-classified information to the Chinese and Mac receives the Meritorious Service Medal for her TAD assignment while continuing to search for the young Indonesian girl she befriended during the siege.