Following Callen's public shooting of the Chameleon, all is not well with the NCIS: LA team, as Callen is placed on suspension and Hetty adjusts to retired life.
A drone strike on a bomb-making compound in Afghanistan leads to the discovery of a retired Marine's remains.
The team investigates an intel operation after four people connected to the project die in a diner explosion.
When a U.S. senatorial candidate's staffer is run over and killed while crossing the street, the team must determine if it was an accident or a murder than could put others in danger.
A CIA agent who once worked with Sam seeks his help before dying of an apparent suicide; while working under cover, Deeks and Kensi enter a prized poodle in a dog show.
A CIA agent's death leads the team to a group of dangerous Russian agents; Hanna worries a secret will be exposed.
The team investigates potential links among a dead naval tech scientist, a surfer and an Internet video; Kensi and Deeks go under cover as they pursue suspects.
As the team investigates the murder of a wealthy, retired CIA agent, Hetty's knowledge of the case is questioned.
Gunmen in costumes orchestrate a strange and brazen heist that could impact the U.S. economy; Granger insists on a partnership with a hesitant Kensi.
Sam, Callen, Deeks and Kensi spend Christmas on an aircraft carrier investigating an NCIS special agent's death; Eric and Nell celebrate the holidays at headquarters; Hetty goes on a trip.
One of Deeks' former defendants is targeted for uncovering information that could dismantle a car shipping operation with ties to a global terrorist ring.
Suspicious of a cover-up, a Marine's widow asks Sam and Callen to investigate her husband's last battle; the team thinks another evaluation is on the horizon.
Callen must infiltrate a network of Chechen terrorists who are recruiting fighters to join their cause as they plan their next attack on the U.S.
The members of the team go under cover as an elite tactical force in order to investigate a crime linked to a cartel kingpin.
An investigation leads the team to question the only survivor of a terrorist organization; Deeks and Kensi follow a trail into the woods.
Sam helps an Afghani elder and former friend search for his missing nephew; Callen worries that Sam is overly invested.
Sam fears for his family's safety when his wife is called to resume a former CIA cover after a case suggests ties to the infamous Sidorov and his stolen nuke.
Callen and Sam work with NCIS: Red, a mobile team of agents, when a murder weapon in Idaho matches one used in a national security case in Los Angeles.
The Los Angeles team and NCIS: Red continue their urgent search for an elusive terrorist before he disappears.
The team investigates when cyanide in a communal water jug kills a lieutenant and leaves a Navy pilot in serious condition.
When the body of a cartel boss is stolen after a successful special task force mission, the team investigates a potential leak and find the missing remains.
When a woman connected to a bizarre case turns out to be an undercover agent from Hetty's past, Callen questions Hetty's motives.
Deeks goes under cover to find information on a notorious arms dealer trying to get back in the business.