Nell joins Deeks in the field on a case involving a former Marine who is being tracked by al-Qaida after embezzling money from Iraq.

The NCIS team tracks a highly skilled assailant determined to avenge her father's death by killing a Brazilian diplomat.

Callen, Sam and Nell must find pieces of a failed rocket launch, including a top-secret government device; Hetty tries to help Keane acclimate to life in the states.

The NCIS team is in danger after their pictures, as well as Mosley and her son’s names, are included on a cartel hit list. Also, NCIS Deputy Director Louis Ochoa arrives with Special Prosecutor John Rogers to interview Mosley about the off-the-books mission in Mexico.

After Anna Kolcheck escapes from prison with her cellmate, Callen and the NCIS team assist with the investigation and search for her whereabouts.

Callen and Sam travel to San Francisco to search for Beale after he's kidnapped during a clandestine mission for Hetty.

While Sam investigates the murder of an Iranian exile working to overthrow the current regime, he must also try to save Agent Rountree, a new agent who’s having an unexpectedly adventurous first day on the job, when he accidentally triggers a bomb. Also, Nell makes a decision about her future with NCIS.

While NCIS must track down an organized crime leader who is trying to buy stolen defense technology, Callen goes to Anna to ask the ultimate question. Also, Deeks is kicked out of NCIS training only to find that Hetty has a life-changing surprise for him.

NCIS obtains a hard drive containing a realistic deep fake video of a deceased terrorist and must retrieve the dangerous technology behind it. However, when the team’s comms are highjacked during their mission, they find that one of their own has been a victim of its potential.

Sam and Kilbride clash when a case involving an arms dealer responsible for the slaughter of ATF agents leads them to a well-connected colonel and friend of Kilbride, accused of supplying militia groups with guns. Also, Kensi and Fatima go undercover at a rehab facility to question the arms dealer’s girlfriend.

As Callen continues hunting Katya, Kilbride enlists NCIS to help find a truckload of stolen guns. The assignment becomes more challenging when their suspect, the son of a mob boss they believe was planning to sell them, is found dead.