When a Russian sleeper agent is identified living within a local gated community, Kensi and Deeks move in posing as a newly married couple hoping to shut the agent down.
G and Sam return from an investigation in Honolulu with some friends in tow. Together they go on the hunt for an epidemiologist intending to unleash the smallpox virus.
When a bomb goes off in the truck of a former Marine officer, who proceeds to flee from the scene, Granger orders the team to find out why they did not know of the man's plan.
A group of Marines discover the mutilated body of a Navy ensign, and when Callen and the team investigate they find leads pointing to a SEAL. Sam refuses to believe the evidence.
A man comes under gunfire while desperately trying to enter the Vietnamese consulate in LA. The team investigate, and discover something interesting in the man's personal effects.
Kensi survives being shot and goes on the trail of her attacker. The rest of the team are hard on their heels, but will they catch up in time to stop any more violence?
Granger summons Kensi to the boathouse, and Hetty summons the rest of the team to the ops centre. Marines are being killed, and Granger believes Kensi is involved.
A violent raid on an armoured truck just outside LAX leads Callen and the team on a hunt for a mysterious wooden crate. G and Sam celebrate five years of service together.
Two Sudanese informants are on their way to give a deposition when the car they are being escorted in is attacked by an unknown assailant. Callen and the team investigate.
A man working for a think tank on the DoD payroll dies by a gunshot would, apparently self-inflicted, from his wife's gun. G runs into serious trouble with an authority figure.
A college a man steals an experimental electromagnetic-pulse weapon, which has the capability to render disastrous damage. Callen and company investigate.
Deeks appears to shoot an unarmed suspect during a sting operation, leading to his dismissal and the LAPD cutting ties with NCIS. But is everything really as it seems?
Sam goes missing in Sudan, along with a gaggle of undercover CIA operatives. G heads out to Khartoum to track them down, while the gang in LA deal with a mole.
Two men are dead and a third is missing, along with a small plywood box containing something of great importance. Can Callen and the team track it down and avoid a disaster?
A Marine attacks a Japanese tourist, who later dies in hospital. Callen and the team investigate, and uncover a complex and troubling situation requiring extreme tact to deal with.
A former Naval Intelligence office is shot to death by an unknown assailant, leading the team on an investigation into the murky and dangerous world of espionage.
While taking down a pawn shop operating as a front for a Mexican drug cartel, the LAPD stumbles onto a dangerous terrorist connection and contacts NCIS for help.
The team investigates when a journalist is gunned down on the Venice seafront, after receiving death threats from Libyan nationalists for a report on an anti-Gaddafi rebel.
In Beverly Hills two masked thugs kidnap a wealthy and successful software developer, so Callen and company help the National Security Agency to get him back safe.
The team head to a beach town on the Black Sea in Romania to investigate the Comescu family, who may be holding the kidnapped Hetty hostage in their grand home.
While working undercover as Chippies, G and Sam come face-to-face with the man responsible for running a gang of dirty cops, and must do whatever it takes to bring him in.
The Callen team are called in when The Pentagon declares a security breach after an online transfer of a file believed to contain classified documents.
While medical examiner Rose conducts a postmortem exam, two intruders blow away her assistant and steal the corpse she was working on. The Callen team is called in.
After a shooting, a recently discharged Navy lieutenant suffering from PTSD asks the NCIS. Callen and the team investigate, and discover not everything is as simple as it seems..
The search for the "little black book" continues. Nell finds a key, and Kensi is kidnapped by Russians. While Deeks heads off to rescue her, Hetty tells Mattias about the book.
A limousine is ambushed, and two men are shot dead. Hetty, revealing that the target was a Swiss black marketeer, convinces the LAPD to allow her to take over the investigation.
The body of a former Delta Force operative turns up brutalised after the man was seen being kidnapped by two thugs. G and Sam follow the trail all the way to Afghanistan.
A Marine reservist and a plastic surgeon are killed in a hail of gunfire, and a woman connected to the event is missing. Will the NCIS team be able to figure out what happened?
Panic comes to downtown L.A. when a lone armed woman seizes a Navy recruiting office. G recognises her from his CIA days, and figures there is more going on than meets the eye.
The clock is ticking when an unknown outfit kidnaps the 14-year-old daughter of a Navy commander and bury her alive at an undisclosed location. Can Callen and the team save her?
The NCIS team are on the case when the body of a man believed to have been a clerk in a Naval intelligence operation is found in the back of a car near L.A., minus one hand.
When three Marines are abducted on the US-Mexico border, Callen and company are called in. A man who was patrolling with them reveals that one of the missing Marines is pregnant.
When and NCIS agent is murdered, G corners the killer at LAX and strikes a risky deal. Using the information obtained, he hopes to infiltrate the organisation behind the murder.
Deeks disappears while on an undercover assignment for the LAPD; Hetty offers help, so Callen and company lend a hand. Elsewhere, Eric follows a trace to a Serbian criminal.