The team is assigned to track down a missing unmanned aerial vehicle (UAV) after it is compromised during a training exercise killing a marine before it disappears.

Callen races against a ruthless adversary to locate a woman who knows the whereabouts of a forgotten fortune earmarked to fund a new war in the Middle East - and also holds the tantalizing key to his unknown past.

The team investigates the murder of a Marine who had top-level security clearance, and the corpse is missing a hand.

Hetty and the NCIS team continue to search for an elusive book that has the attention of several foreign security agencies.

The team looks for the person responsible when classified pentagon documents are uploaded to a blog site.

Sam resumes a former alias and boards a one-way flight to Yemen in hopes of tracking down a terrorist group's leader and rescuing the hostage son of a Saudi Prince.

The Special Projects team travels to Romania to search for Hetty, while delving into the history of the Comescu crime family, and their connection to Callen.

The NCIS team must determine whether a dishonorably discharged Marine is the target of an international set-up or if he committed murder

A new Assistant Director is assigned to oversee LA operations for NCIS, the team begins to wonder what his intentions really are.

The joint NCIS: Los Angeles and Hawaii Five-0 task force travel from Hawaii to Los Angeles, when the lead suspect in the case moves to the mainland with a deadly virus in tow.

The crossover starts on Hawaii Five-0 S02E21 Pa Make Loa (Touch of Death) (I).

Eric witnesses his friend, a computer systems expert, being attacked by people who want information that could redirect a missile; Kensi runs into a familiar face in Afghanistan.

After the U.S. Treasury Department is hacked, Nell and Eric go undercover inside a couple's retreat to track a tech-savvy husband and wife linked to the crime. Also, Digital Forensics Specialist Dave Flynn (Scott Grimes) arrives from the NCIS cyber office in San Diego to run ops while Eric and Nell are on assignment.

After months of planning, the NCIS family celebrates the wedding of Kensi and Deeks. Also, an old acquaintance, Anatoli Kirkin, pays Deeks a surprise visit on his wedding day and he isn’t alone.

The team assists the DOJ in the investigation of an arsonist who targets an FBI safe house that's protecting a political activist seeking asylum; Eric deals with the aftermath of Nell leaving the team.