After a highly decorated Navy Captain, Charles Langston, kidnaps a Veterans Affairs administrator who has been siphoning funds, the NCIS team must work with Hetty’s former Vietnam War colleagues, now-retired Admiral AJ Chegwidden and Admiral Sterling Bridges to solve the case.

Sam goes undercover as a day trader after a prominent investment banker with ties to a Russian oligarch is murdered. Meanwhile, one of Callen’s aliases is the victim of credit card theft, and Mosley is concerned it signals something bigger.

Callen and Sam join forces with Anna Kolcheck and the Bureau of Alcohol, Tobacco and Firearms (ATF), when Arkady Kolcheck warns NCIS that a notorious international weapons dealer has returned to the states. Also, the case requires Eric to go undercover as a bank IT technician.

NCIS partners with the FBI after a Marine is murdered by a rare nerve gas. Also, Deeks shares his dream to quit law enforcement and open a bar.

While assisting NCIS with an undercover operation, informant Elizabeth Williams is arrested and the team is unable to provide her with an alibi. Also, Callen meets with ATF Agent Anna Kolcheck who remains on suspension following her last joint case.

An elaborate bank heist to steal a single safe deposit box held by Veronica Stephens, a Navy contractor, leads NCIS to investigate her corrupt consulting firm.

Sydney turns to her sister Nell for help after her high school crush, Andre Martinez, is mixed up in a Russian plot to steal intelligence from the Department of Defense. Also, Special Prosecutor John Rogers conducts mandatory performance reviews with the team.

The NCIS team searches for a stolen painting valued at $40 million after online chatter indicates the artwork is being sold on the black market to fund terrorist activity.

The NCIS team investigates the murder of a Naval warfare engineer at a spoken poetry event. Also, Callen asks Nell to assist him in a worldwide search for Anna's whereabouts.

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.

As the trial begins of a Chief Petty Officer who Callen and Sam arrested for war crimes last year, the NCIS team is called to help find the missing star witness.

When Sam’s daughter Kam is kidnapped after leading citywide protests he will stop at nothing to find her. Also Deeks rejoins NCIS and Callen searches for answers about Anna

When military grade technology is stolen, a deaf engineer, Sienna Marchione, who always wanted to serve her country, and the only member of her team to survive the theft, helps Kensi and NCIS track down the tech before it’s taken out of the country.