The NCIS team investigate the brutal murder of a navy lieutenant, recently returned home from the Middle East.

Gibbs continues to work with Captain Westcott, as he retraces his steps to assist the team in tracking down a terrorist.

A serial killer claims to have information about the murder of young prisoner who was found dead in the bathroom just before he was released. Meanwhile, Frankie Jr gets ready to take the detectives exam.

A patient with a ghastly ailment seeks a cure at the hospital; Chad finds a secret of Brock's.

Dean Munsch, Denise and the Chanels question Hester and the survivor of the Halloween massacre.

The team tries to talk to a young man, who is found in the street covered in blood and believes he has murdered someone.

Dean, Denise and Hester create a plan to catch The Green Meanie by throwing a Halloween party.

Sutton encourages Ethan to bond with his estranged father, while Emma works to prove his innocence; Rebecca offers Laurel the chance to produce a music demo.

The team investigates when the teenage son of a Secret Service agent disappears. They discover a long-festering secret that sets in motion a deadly chain of events. Recurring guest star Steven Weber appears as Clark Medina.