In the wake of Ziva's disappearance, the team works to figure out what happened, even as Tony grows to suspect the validity of their earlier findings.
As the team investigates a series of murders at a bachelor party, they soon come to discover that there is more to the victims and the party than what meets the eye.
As Ziva makes a career choice that hinges on Gibbs' approval, the team investigates the murder of a blogger who once cast doubt on the integrity of one of their investigations.
The circumstances surrounding Ziva's captivity come into question when the discovery of a body and the arrival of a familiar face cast doubts on her.
When a suicide turns to be anything but, the team is forced to look into the background of an entire naval squad, as well as the victim's wife, to figure out who tried to stage a murder to look like a suicide.
When Gibbs becomes a part of an ongoing investigation when bodies are found on his boat, his search for the truth gets him entangled in a family feud gone south.
Director Vance finds himself embroiled in the murder spree of a North Korean assassin seeking revenge on those who wronged her.
In the wake of a blackout, the team faces a unique challenge when they have to investigate a murder without the use of their regular equipment.
An investigation at a military base leads the team to uncover a conspiracy to sell secret military code, putting the life of a child prodigy on the line as she gets on a killer's radar.
With Christmas approaching, various team members try to juggle their personal relationships with the investigation of a murder that reveals a family's complicated dynamics.
The discovery of a scorched body in the wake of a forest fire sets to investigate the suspicious incident that was made to look like an accident.
An assassination attempt on a Saudi prince leaves the team to navigate a terse political situation as they uncover the prince's complicated relationship with his retinue and his family.
The team pulls out all the stops to protect a government witness from her would-be assassin who is trying to eliminate her en route to prevent her from giving her testimony.
As a terrorist threat hangs over DC, the team struggles to find the source behind the alleged dirty bombs before catastrophe strikes.
When the investigation of a murder leads to the uncovering of a ring that deals in expensive car parts, Tony and Ziva go undercover in an attempt to find the ringleader.
Gibbs is forced to confront his traumatic past when a case hits too close to home, leaving him to make a difficult decision as he tries to balance his career with his personal feelings.
In the wake of a shooting, the team discovers that their victim went MIA years ago, only to assume a different identity and lead a completely different life.
The murder of a Navy diver forces the team to join forces with the Coast Guard as they seek to uncover the mystery of the crime.
As Gibbs makes a controversial decision that causes tension within the team, they are forced to shelve their protests as they go into the world of prostitutes to find a killer.
When several FBI informants end up dead, Gibbs recruits Agent Fornell to help with the investigation, which leads them to a private security company that may hold answers to the truth behind the murders.
As Tony struggles with his attraction towards a victim's sister, the team has to race against the clock to figure out the truth as it's revealed that the siblings may be connected to a foreign intelligence agency.
As the team hunts for a possible serial killer, Abby learns a disturbing truth about Gibbs, leaving her torn between her duty and her loyalty to him.
When one of their own is found murdered, the investigation takes a personal turn for Gibbs as he seeks to find the killer of his friend. But little does he know that the case is connected to another that may threaten his career.
As Gibbs finally comes to learn the identity of the person who has been after him, skeletons from a 20-year-old case return to haunt him, putting everyone and everything he cares about on the line.