Deeks disappears while on an undercover assignment for the LAPD; Hetty offers help, so Callen and company lend a hand; Eric follows a trace to a Serbian bad guy; Deeks shows up and solves the case, and the team get him out of a tight spot.
In Cyprus an NCIS agent dies by murder; the killer lands at LAX, and G grabs and questions him and obtains information through a deal; G infiltrates the hit squad for the next lethal action; the team solve the puzzle and nab the bad guys.
On state-owned property near Imperial Beach, California, south of San Diego, while four Marines patrol the area (along the US-Mexico border) to support federal customs and immigration agents, unknown people for unknown reasons ambush the Marines and their Humvee; one escapes, and three remain missing; officials wonder whether the intruders are Mexican smugglers; Callen and company investigate. A search party finds the body of one Marine; the lone survivor says that one of the missing is a pregnant lance corporal, and the dead one was the father; a snitch gives a tip ...
In a parking garage on Rodeo Drive in Beverly Hills, California, near Los Angeles, two shoppers find the body of a man less a crudely severed hand, which is missing; the victim was a Marine corporal, stationed at Camp Pendleton and assigned as a clerk in the G2 (intelligence) office with a top-secret clearance; Vance has expressed interest, so Callen and company investigate. Nell, an enthusiastic new analyst who finishes the sentences of others, has arrived for duty. Eric and Nell see a clue about the amputation; the musketeers conduct interviews; Eric and Nell find ...
One or more people kidnap the 14-year-old daughter of a Navy commander and bury her alive inside a wooden box; the FBI and the Callen team investigate; Sam empathizes; G and Callen catch the bad guys and rescue the daughter, still alive.
In downtown LA a lone armed woman seizes a Navy recruiting station; G recognizes her as his former partner while undercover for the CIA; she asks for his help and gets it; the team find the bad guy responsible plus the rest of the story.
Two men, a Marine reservist and a plastic surgeon, die by gunfire, and a woman disappears; Callen and company investigate; Eric and Nell provide clues, and the team go to a party, where they grab the bad guys and prevent any damage.
A sergeant first-class retires from the Army and the Delta Force; two thugs snatch him, then later his tortured body turns up; Callen and company investigate; G and Sam go to Afghanistan, bag the bad guy, and return with tea for Hetty.
In Hollywood two men ambush a limousine and shoot the occupants to death; Hetty says that the target, Renner, was a Swiss antiques dealer and black marketeer; she persuades the LAPD to allow her to take over the investigation because of the nature of a little black book, which she believes is the object of the activity. While Hetty visits a man in an assisted-living place, G and Sam visit Renner's pad, which someone has tossed; Eric identifies a man, Lee, who appears in a number of photographs around Renner's house; G and Callen visit Lee's office and break up a ...
Intrigue and violence continue while several interests search for a "little black bloody book"; Nell finds a key, Russians kidnap Kensi, and Deeks rescues her; Hetty tells Mattias about the book; G, Sam, and Deeks give Mattias a promise.
A recently discharged Navy lieutenant and intelligence officer, diagnosed with PTSD, asks for help after a shooting; Callen and company investigate; not everything is as it first appears; the team find the pieces and put them together.
While Rose, the medical examiner, conducts a postmortem exam, two intruders blow away her assistant and steal the corpse and a van, but Rose evades; she calls the Callen team, who investigate because of an apparent Navy connection with the body. Kensi and Deeks check out the abandoned van; inside they find something exciting; they also see the victim's pad and his girlfriend. A Navy commander briefs the team about a highly classified new system for tracking people; he assures them that it does not exist anywhere inside ConUS, but suddenly it does exist and function in...
The Pentagon declares a breach after an online transfer of a file believed to contain classified documents; the Callen team, investigating, find the sailor involved, who reveals the keyword, but the file contains something very different.
Inmates initiate Moe by beating him inside a federal prison; Sam goes to him and undercover; Kensi and Deeks find a device and a plan; Hetty says there's more; an escape takes place, Sam loses someone, and a larger plan moves on. [Cont'd.]
Inside his pad by night G grabs a prowler, who works for Arkady, who gives G a tip; Kensi and her buds run a scam on a foreign businessman; G gets into a firestorm, but the rest of the gang show up and lend a hand.
G and Sam, undercover as Chippies, continue to pursue certain dirty cops; they meet the head man and his goons, whom Eric IDs; G and Sam encounter a major problem and lose their bikes, but the team grab the bad guys and a chick physicist.
While Deeks follows his morning routine, during what appears to be a holdup of a convenience store, a gunman shoots him twice in the chest with a pistol; Deeks goes into surgery; G and Sam investigate at the scene; Kensi waits at the hospital; Eric and Nell prompt their computer. The team realize that two bad guys had staged the supposed robbery as a deliberate ambush; Eric traces the suspects' car to the hospital, where G and Sam see it and engage them; the driver dies, and the other man escapes but winds up at the boat shed. The team set up G for an undercover meet;...
One of Sam's aliases receives an invitation to Yemen to meet Abdul; Hetty hopes that Abdul will lead them to Saadat, Abdul's brother, believed to be a leader of terrorists; G and Nate provide backup; the team support, and it all works out.
A Latino day laborer dies, and a lieutenant commander in Naval intelligence disappears; Callen and company investigate; G and Sam find evidence suggesting an assassination plot against a visiting Venezuelan politician; the team thwart it.
A major player in the private-sector aerospace industry dies inside a test chamber at his facility; Callen and company investigate; Eric goes undercover as an FAA inspector; a big bang occurs; the team grab the bad guys at a flea market.
After a key witness, Ray, testifies in a federal arms-trading prosecution, he retires as an informant; the team give him a new identity, Charlie, and direct him to a new location; next Callen and company turn their attention to the missing military weapons; however, within two hours Charlie disappears after a shooting in Los Angeles; Deeks goes back undercover while the other members check out the scene. Kensi and Deeks chase around with Ray; a firefight breaks out, and Kensi takes out one shooter, but Ray disappears again; G and Sam seek entertainment and find some, ...
An unident man dies after a beating and a burning; a specific radiopharmaceutical in the body implies a connection to a previous case; Callen and company grab the bad guy. Hetty resigns, disappears, and reappears in Prague. [Continued.]
Hetty turns up in Prague and proffers a message. G and Sam investigate; Eric and Nell help. G, Sam, Kensi, and Deeks go to Prague, find a lead, and follow it to Romania, where G has a flashback, and Hetty delivers the message. [Continued.]