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.
Gibbs is forced to dig into the past when a murder of a Marine and his two friends turns out to be linked to past issues. Meanwhile, Gibbs faces a tough challenge as he holds Ziva's fate in his hands.
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.
The NCIS team is called in to investigate the murder of a Marine found halfway around the world, and the investigation takes a surprising turn when Ziva turns out to be connected to the deceased Marine.
When a Marine known for his love of practical jokes is found dead on Halloween, the NCIS team is called in to investigate, and they soon learn that his jokes may have been the reason why someone killed him.
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.
When an attempted robbery leaves a Lieutenant dead and the entire city without power, the team must figure out what happened through old fashion methods.
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 NCIS team is called in to investigate the death of a reverend's enlisted son, and they soon realize he may have been the victim of a hate crime. Meanwhile, Gibbs tries to figure out why his father had a sudden change of behavior when he comes to visit during the holidays.
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.
Anthony DiNozzo Sr., father of Tony gets involved with a case concerning an assassination plot against a prince. The elder DiNozzo's link will cause Gibbs to doubt whether Tony can remain impartial in the investigation.
In order to solve a case, Tony and Ziva are sent packing to the most romantic city in the world, Paris! The hotel screws up their room reservations and accidentally has them share a room.
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.
The team investigates 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.
Gibbs asks Holly Snow to help them to investigate a murder in the world of professional call girls, which will cause troubles for the Team.
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 NCIS has to find a serial killer, and their investigation leads them to a surprising revelation. Meanwhile, McGee tags along with Abby to the south of the border, where Abby has to make a speech.
The NCIS team comes to a surprising discovery while investigating the shocking murder of their own team member.
In the conclusion of a two-part finale, Gibbs heads to Mexico for a showdown with a drug cartel intent on revenge. Gibbs has to reassess the rules by which he lives when he is forced to make a devastating choice to save the lives of his team.