[WATCH] 'NCIS' Sneak Peek: A Case Falls on the Roof of the Squad Room

Something's going on at headquarters in NCIS season 15 episode 18, and it looks like the dead body and bomb materials found on the roof of the squad room, which leads to an evacuation, is just the beginning of the team's troubles.

Also in "Death from Above," the team reads the first draft of Ducky's book, and while it's long, it's just the beginning.