Callen takes on a secret project, leaving the team in the dark; when Hetty shuts down Callen's operation, the team must locate him before he gets in trouble.
When DEA Agent Talia Del Campo's (Mercedes Mason) partner is murdered, she turns to the team for help; Kensi thinks Deeks is hiding something.
The NCIS team investigates a Peruvian massacre that occurred 20 years ago after it learns that a fashion model, who may have survived the incident, may now be in danger.
When Sam and Callen receive a cellphone, the caller threatens innocent lives if his instructions are not followed.
When NCIS Special Agent DiNozzo's prisoner escapes custody, he turns to the Los Angeles team for assistance.
Sam's former partner, Ruiz (Anthony Ruivivar), goes missing while purchasing a dangerous explosive during an undercover operation.
Kensi and Deeks pose as cult members in hopes of rescuing a former Department of Defense employee who was persuaded to reveal classified information.
A woman named Jada, led to asylum by Sam four years earlier, goes missing; Kensi and DEA Agent Talia Del Campo (Mercedes Mason) go under cover.
The members of the team search for a teenage girl who may have been recruited by a terrorist organization.
The team races to prove that Deeks is innocent when he is arrested for the murder of his former partner.
A truck transporting Christmas trees hits a suspected North Korean spy; Kensi and Deeks try to include their mothers in their plans for Christmas; Hetty thinks Granger is not in the holiday spirit.
When a gunnery sergeant moonlighting as a security guard at a decommissioned nuclear power plant suffers radiation poisoning, the team goes under cover to investigate.
A tech entrepreneur and venture capitalist who secretly developed a computer program that stealthily collects data is murdered.
Kensi and Deeks announce that they are moving in together right before they are assigned to protection detail for Kensi's ex-fiance, who has a list of important contacts that people are willing to kill for.
The team goes under cover with Arkady's daughter at a Los Angeles gala to gain access to the Russian Consul General's computer.
While in Russia, Callen, Sam and Anna try to break Anna's father and a CIA agent out of prison; Callen makes a discovery; Eric goes on an assignment with Kensi and Deeks.
A discovery sends Callen and Sam to Africa to investigate; Sam's family is transported to a safe house.
A Cuban spy escapes custody before a scheduled prisoner exchange with his country; Kensi learns that Deeks thinks she's too messy.
The team try to rescue a child who is in danger after being brainwashed by a terrorist.
The team searches for a North Korean spy while assigned to protective details for the commander of the Pacific Command.
Operational psychologist Nate Getz's loyalties come into question when he fails to make contact with Hetty while working under cover to establish a link between organized crime and terrorism.
Granger escorts Jennifer Kim to Los Angeles; while being questioned about a North Korean spy, Jennifer admits to Granger that she knows he is her father.
When secret information about suspected terrorists goes missing from a secure Department of Defense container at the site of a fire, Sam and Callen must go under cover to investigate.