As the hunt for Ziva's replacement begins, Gibbs and his remaining team members must head back to work with the past still weighing heavily on their minds.

The team must take a second look into the death of a Lieutenant after the blogger who accused them of a cover-up ends up dead.

When a Marine's body surfaces halfway around the world, the investigation forces Ziva to dig up a buried chapter of her life.

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.

A murder investigation prompts Gibbs and the team to play family counselor to his former mentor, Mike Franks, in the hopes of preventing a bloody international conflict.

With the team's help, Vance faces his demons while uncovering a complex relationship with a killer that puts his whole family in danger.

The team literally finds themselves in the dark when the investigation into the death of a Lieutenant is connected to a city-wide blackout.

A dead Marine's day job at a government think tank leads Gibbs and the team into the life of a 12-year-old prodigy who may be the killer's next target.

The body of the son of a retired Colonel-turned-preacher is found and the team have their suspicions that he may be the victim of a hate crime.

When a Navy pilot is found dead under strange circumstances in a secluded area, the team finds themselves battling a no-nonsense attorney with a hidden agenda.

Gibbs is worried about Tony's ability to handle his job when Tony's father turns out to be linked to their newest investigation, an assassination attempt on a foreign prince.

While on the flight back from Paris, Tony and Ziva realize that their assignment to protect a government witness in an embezzlement case is in great danger when they learn that an assassin is located on the same flight.

The team finds themselves in a race against time when a terrorist group threatens to detonate a "dirty bomb" in the D.C. area.

When a Marine is found dead, Gibbs, Fornell, and the team hit the open road to bust an illegal trucking operation.

Secrets arise when Gibbs' former mother-in-law surfaces as a witness in a murder investigation.

Gibbs and the team investigate the shooting of a Marine and uncovers more to his life than anyone would have ever imagined.

The team discovers striking similarities between themselves and their CGIS (Coast Guard Investigative Services) counterparts when a Navy diver seeking sunken treasure is found dead.

The death of a Navy officer leads Gibbs and the team into the world of high-priced call girls, relying on D.C. Madam Holly Snow to help them catch a killer.

When an NCIS polygraph specialist's night job takes a dangerous turn, Gibbs, Fornell, and the team have to uncover the truth.

DiNozzo finds himself increasingly captivated by a woman he's never met while investigating the murder of her brother.

The team tries to track down a serial killer, while Abby heads south of the border to give a speech with McGee in tow.

When a colleague's murder sends shockwaves through the team, Gibbs uncovers a surprising link to the crime.

Gibbs heads to Mexico to face his demons and make a startling decision.