Plot

A naval cryptologist is found dead shortly before she is scheduled to be interviewed at NCIS about a mole in her department. All signs point to suicide, but the timing seems too coincidental for Gibbs's gut.

While searching for a mole, Tony and Ziva go to the home of a woman Navy lieutenant and cryptologist; they find her shot to death, apparently by suicide; Gibbs and the gang investigate. Abby shows that a second person was present when the victim died, and McGee traces the pistol to a workmate of the victim. An item has disappeared from the workshop, but Gibbs finds it. Fingerprints implicate a member of the staff of an embassy in Washington, but the suspect has diplomatic immunity; McGee learns that the suspect is about to leave the USA. Gibbs feels uneasy, so he gets Abby to do some more lab work, which pays off, then Gibbs loses the mole but arrests the killer.—DocRushing