NCIS: Season 8, Episode 19

8 - 19: Tell-All

A dying message from a naval officer attached to the Defense Intelligence Agency leads Gibbs' team in search of a manuscript containing military information. As the team investigates further, they find the body of a murdered FBI agent, and discover that both victims were involved in the writing of a book exposing secret anti-terrorist operations. However, the team is forced to track down the anonymous author of the book when Navy intelligence officers destroy all copies of the book. With the author's help (who is also a former Marine Lieutenant who was discharged for a failed anti-terrorist operation), the manage to arrest an arms dealer who had stolen a shipment of military weapons, but find out that she wasn't the killer. With this new information, as well as new evidence from Abby, Gibbs deduces that the FBI agent's husband is the killer, since he mistakenly believed that his wife was having an affair.