As NCIS investigates a dangerous connection between the Nexus cartel and Parker's longtime nemesis, mob boss Carla Marino, the team uncovers a high-stakes plot involving stolen nuclear material. With time running out, Parker is forced into an uneasy alliance that could determine the fate of the operation - and his own future.

McGee's career and credibility are on the line when he investigates the deputy director for corruption. Also, Torres and Knight receive some surprising news.

When a trio of combat vets are found murdered in a D.C. motel room, NCIS tracks down a suspect who refuses to talk to anyone but Sam Hanna.

After NCIS captures the hitman known as "The Poet," the team races to uncover who ordered the assassination of a Navy chief.

A girls' night out takes an unexpected turn when NCIS is called to investigate the motive of a possible arsonist. Also, Torres struggles to find work/life balance.

After a Navy Lieutenant's death reveals ties to Special Agent Sawyer, Torres and Knight uncover a murder linked to a wealthy family. Meanwhile, Parker discovers a shocking connection between his mother's death and Lily.

When Torres receives a text from Jimmy's daughter who has discovered a large sum of money near the naval library, the team works together to investigate.

NCIS investigates the case of a Navy lieutenant found dead at a blood donation bank. Also, McGee needs help from the team to raise money for his twins' school fundraiser.

NCIS investigates the fatal poisoning of one of Kasie's forensic scientists. Meanwhile, McGee is questioned by the Pentagon regarding the contents of his book.

NCIS stages a fake wedding for two of its own in an attempt to take down the mob.

After NCIS learns that the owner of Parker's favorite bakery is being blackmailed, they hatch a plan to save her.

When a shocking tell-all threatens to ruin Christmas for a decorated Marine, NCIS must unwrap the truth and deliver a holiday miracle — before the book hits shelves and turns a hero's legacy into a holiday disaster.

NCIS investigates a murder related to a car that begins driving on its own. Also, Parker is still seeing visions of Lily.

Torres receives intel from a confidential informant regarding top secret naval information that's at risk of being sold.

Things become tense when Knight is assigned to protect his wife after the home of a high-level defense contractor is attacked.

NCIS works with the CIA to discover what secrets are being kept by Captain Butler, an aging former spy.

After receiving intelligence on deadly threats to multiple locations that could lead to a catastrophic war, NCIS is called in to try to neutralize the danger.

NCIS is called in to investigate when a lieutenant returns home on Halloween Eve to find a surprise party being thrown for someone else at his home.

As Vance prepares to host diplomatic talks with Venezuela, the team is called in to investigate the dead body of one of his inside men.

NCIS searches for a missing undercover agent in the midst of an active hostage situation.