The team races against time to save a Naval Commander's daughter after seeing a video of her being buried alive.

Hetty and the NCIS team continue to search for an elusive book that has the attention of several foreign security agencies.

Sam goes undercover as a prisoner to track down a terrorist group responsible for several bombings around the world.

When an attempted robbery takes place at a secure facility on a Marine base, Kensi must determine what the thief intended to steal.

When a Navy ID is found on a dead body tied to a hazardous material smuggling case, NCIS is granted permission to investigate in Mexico and asked to help locate the missing materials.

After Sam’s undercover mission in Sudan turns deadly, Callen and the NCIS team must track down their missing agent before it is too late.

With Assistant Director Granger critiquing every move, the NCIS team must track down a chameleon-like killer who has evaded law enforcement agents, including their very own Special Agent G. Callen, across several countries.

When the body of a Navy Intel Officer is found, evidence points to a team of Navy SEALs who are about to depart on a hostage rescue mission, leaving former Navy SEAL Sam Hanna to interrogate the group and possibly compromise the mission.

When a CIA agent who worked with Sam Hanna over eight years ago seeks his help and is soon found dead of an apparent suicide, Hanna and Callen suspect foul play and a bigger conspiracy. Meanwhile, Deeks finds his inner “dog whisperer” with Kensi as the two go undercover and enter a dog show with a prized poodle.

After an NSA analyst is found eaten by a shark, the team's investigation leads them to a cartel's money-laundering scheme and sends Callen into a mental asylum to find a key witness; Kensi struggles with her therapy.

After Sam's wife, Michelle, is taken from her home, the kidnappers demand the prison release of Tahir Khaled, Sam's arch nemesis, in exchange for information on her whereabouts.

Kensi is transported to a missile launch facility to help thwart a takeover of nuclear weapons.

While investigating a missing person’s case, the team uncovers a killer who puts on shows for high-paying voyeurs. Also, Mosley assigns Callen as her partner on a joint ATF mission to apprehend someone from her past.

Gravely injured and unable to communicate with the team in the U.S., Callen, Sam and Kensi, with an unconscious Deeks in tow, search for a safe way home as a cartel boss places a “dead or alive” bounty on their heads. Also, Mosely and retired Navy Admiral Hollace Kilbride beseech their contacts in Mexico and D.C. for assistance with their missing colleagues

Deputy Director Ochoa volunteers the NCIS team to assist with a covert operation tied to a terrorist group advocating for extreme military force. Also, Callen has concerns as to what an assignment of this nature could mean for the future of the team.

The NCIS team works with the Global Criminal Tribunal when a Syrian seeking justice, David Sarraf, is brutally attacked while delivering evidence that would prove chemical weapons were used on civilians. Also, Kensi stays at the crime scene and comforts Sarraf who is pinned behind a vehicle.

Callen and Sam work with Navy Captain Harmon "Harm" Rabb, Jr. (David James Elliott) to locate a group of ISIS sympathizers aboard the USS Allegiance. Also, Hetty enlists her friend, Lieutenant Colonel Sarah "Mac". Mackenzie (Catherine Bell), to help obtain information from a Russian diplomat.

Callen and Sam run protection detail for retired Navy Admiral Kilbride in an operation to locate a missing Naval intelligence officer.

The NCIS team reluctantly aligns with two former criminals from England, Ricky Dorsey and Frankie Bolton, after a powerful arms dealer kidnaps Ricky’s daughter in an attempt to obtain a dangerous weapons system.

Sam, Callen and Rountree travel to Afghanistan when Marine Lieutenant Colonel Sarah "Mac" MacKenzie asks NCIS to help with a sensitive case after two SEALs claim their chief murdered an unarmed prisoner.

In order to get intel on a matter of national security, Kensi must come face-to-face with a sociopath who has been obsessed with her since she put him in jail years ago. Also, though Deeks is desperate to keep Kensi safe, he is forced to leave NCIS.

When a Naval Intelligence Officer is tortured and murdered, NCIS must work with Joelle, who informs them that other CIA operatives are being killed in the same way. Also, Kensi receives a threatening postcard from David Kessler, the sociopath who is obsessed with her.

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.

Inom den amerikanska flottans undersökningsbyrå, NCIS, finns en särskild enhet, Office of Special Projects (PPP), som fångar farliga brottslingar som utgör ett hot mot den nationella säkerheten. Med hjälp av falska identiteter och avancerad teknik drar teamet med utbildade agenter på hemliga uppdrag, och ofta sätter de sina egna liv på spel för att få tag på bovarna. Special Agent G Callen är en kameleont som kan förvandla sig till vem som helst för att infiltrera den kriminella undre världen.