When Gibbs meets with a Navy chief petty officer and his attorney (to make a deal), the CPO collapses and dies; the gang investigate; Ducky feels confused about the cause of death; Abby finds the reason and explains it. The victim offered information about an illicit arms dealer, with whom Gibbs then talks, and whom McGee then tracks. McGee also finds a connection between the vic and the dealer. Gibbs and McGee take some flak from the Defense Intelligence Agency; McGee and the probie pick up a hot British chick, and Gibbs catches a smart kid. The more Gibbs learns, the more frustrated he feels. McGee and the probie run into trouble, but that works out. Gibbs finds out and figures out what happened, then he has an interesting chat with the dealer.