Callen returns back to the NCIS Office of Special Projects to solve a kidnapping case.

A case involving the murder of a drug dealer turns personal for Special Agent Sam Hanna when he discovers his former Navy Seal comrades are involved.

The team is assigned to track down a missing unmanned aerial vehicle (UAV) after it is compromised during a training exercise killing a marine before it disappears.

The NCIS team searches Los Angeles for the lead suspect of a murdered Iraqi businessman, a former Marine who had been hired by a private security firm to protect him.

When a United States citizen of North Korean descent is murdered, the secrets to classified software are thought to be lost until NCIS uncovers a suspect from Director Vance's past.

The NCIS team must find a motive when they discover the body of a marine who had been living a double life as a wealthy bachelor.

Following the murder of a Russian woman, the NCIS team uncovers evidence that answers who and why Callen was shot six months ago.

While Hetty is attending a Senate hearing in D.C., the investigation of a murdered Marine Lance Corporal leads the NCIS team to stolen anti-tank missiles and a dangerous militia group.

Forensic scientist Abby Sciuto joins the Los Angeles NCIS team when a murder case resembles the pattern for a serial killer she has been tracking.

As the courtyard is being transformed with holiday decorations, the NCIS team races to solve the murder of a Marine by an exploding cell phone and to find the remaining men of his former EOD (explosive ordnance disposal) unit before another deadly explosion kills someone else.

The death of a Petty Officer leads the NCIS team to a teenager in Sam's life. Meanwhile, Hetty is concerned about the effect that the workload is having on the team.

The murder of a recently released convict forces Callen to go undercover solo as an old alias, while Sam and the LA team track him from a distance.

The team rushes to a crime scene after receiving an "agent needs assistance" page and learns that one of their own is in peril.

A crime scene poses a national security risk when the LA team discovers the location was used to create a deadly toxin which is now missing.

While opening a safety deposit box at a local bank, NCIS Special Agent Kensi Blye is shot after three armed assailants enter and hold everyone in the building hostage.

The death of a lieutenant commander appears to be suicide but the NCIS team uncovers evidence corresponding to murder. Also, Operational Psychologist Nate Getz joins Special Agent Kensi Blye in the field.

After a sailor is killed during an underground street race, the NCIS team determines that his car had been sabotaged and contained confidential Navy equipment. Meanwhile, Callen is forced to take traffic school.

The investigation of a drive-by shooting has the NCIS team searching Los Angeles for the dead marine's younger brother who may be the next target and the one with the answers.

When an undercover operation has the NCIS team investigating a MMA gym and its fighters, Sam Hanna is tasked with donning gloves and entering the cage for a one-on-one fight.

NCIS investigates the murder of a Navy officer entangled in the world of Hollywood glitz and glamour as the team is joined at Hetty's request by LAPD liaison Marty Deeks.

The NCIS team races to save one of their own when they receive video evidence of Special Agent Dominic Vail being held hostage months after he was kidnapped.

The NCIS team is on the hunt for a terrorist who escaped Army custody during a secretive transfer in Los Angeles.

After Callen's cover is blown and compromises the unit, the NCIS team races to find out who is behind the security breach.

Callen races against a ruthless adversary to locate a woman who knows the whereabouts of a forgotten fortune earmarked to fund a new war in the Middle East - and also holds the tantalizing key to his unknown past.

When one of their own disappears while undercover, the team must work alongside LAPD on a case involving human-trafficking, money laundering and drugs.

The NCIS team jumps into action when video surveillance footage shows an ambush on a humvee transporting Marines in the desert. Meanwhile, Nate returns from his mystery assignment.

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

Sam resumes a former alias and boards a one-way flight to Yemen in hopes of tracking down a terrorist group's leader and rescuing the hostage son of a Saudi Prince.

When a former Marine is suspected of creating a chemical bomb, the NCIS: LA team joins the FBI’s domestic terrorist task force including Operational Psychologist Nate Getz.

A distraught widow is suspicious of the circumstances surrounding her Marine husband’s last battle and Sam and Callen help to determine if there has been a cover-up. Meanwhile, Hetty summons Operational Psychologist Nate Getz to be her “pawn” and the rest of the NCIS: LA sense another evaluation on the horizon.

In an effort to help Sam and Deeks return to work, Hetty calls upon Operational Psychologist Nate Getz to help them cope with their traumatic experience. Meanwhile, the rest of the NCIS: LA team investigates the murder of a former Navy Admiral and a controversial journalist aboard a private jet.

Callen and Sam search for a murder suspect -- a retired assassin (Danny Trejo) they encountered on their first case together.

The team learns that someone from their past is targeting one of their own. Nate Getz attempts to help Nell get through a traumatic experience.

After Operational Psychologist Nate Getz fails to check in with Hetty while working undercover on a mission linking organized crime to terrorism, the team learns he is working with an infamous crime leader,

After a Navy reservist is killed while protecting a city councilman, Sam is sent undercover in a private security firm with links to several criminal organizations.

When a Navy lieutenant and his grandfather are kidnapped from a retirement home, the team's investigation leads them to a con artist couple and the hunt for a rare coin; Callen meanwhile has to deal with his father's actions when he kidnaps the father of his grandson (and Callen's nephew).

When a newborn child is found abandoned on a Navy ship, Kensi and Deeks search for the mother on board before she dies of complications. Also, Nate meets with Admiral Kilbride and learns about the CIA project from the ‘70s and ‘80s involving children.

NCIS investigates the kidnapping of Master Sergeant Boomer, a military working dog. Also, Sam looks to sell his boat so he can take care of his father who is suffering from Alzheimer's.

The NCIS team helps Naval intelligence officer Akhil Ali locate a fellow officer who went missing while recruiting foreign assets as potential sources of intelligence. Also, Callen and psychologist Nate Getz track down a man Callen believes was present for his training when he was young.

The NCIS team continues the case with ATF and the stolen weapons. Also, Callen and Anna decide on an impromptu wedding.