When a Marine known for his practical jokes is found dead on Halloween Eve, the NCIS team discovers that the victim’s “good-natured” pranks may have inspired ghoulish retribution. Meanwhile, Ziva tries to adjust to her new role on the team.

The investigation of a Marine’s death on foreign soil forces Ziva to confront her past.

When a blogger that accused NCIS of a cover-up turns up dead, the NCIS team has to find out who killed him and take another look at the closed case.