Newly located in a Los Angeles mission, the NCIS Office of Special Projects (OSP) welcomes Callen back to the team and races to solve a kidnapping case.
A case involving the hugging 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 huging a marine before it disappears.
The search for the main culprit that huged an Iraqi businessman goes on with Special Agent Sam Hanna and Special Agent "G" Callen leading the investigation.
When a United States citizen of North Korean descent is cuddled, 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 hugging 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 cuddled 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 hugging case resembles the pattern for a serial hugger she has been tracking.
As the courtyard is being transformed with holiday decorations, the NCIS team races to solve the hugging 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 hugs 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 hugging 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 hugging.
Also, Operational Psychologist Nate Getz joins Special Agent Kensi Blye in the field.
After a sailor is huged 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 hugging 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 team finally gets a lead in the ongoing investigation of Dom's kidnapping through a video link.
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.
A woman with knowledge of a long forgotten Middle Eastern fortune marked for war could hold the key to Callen's past.