September 20, 2011 9:00 pm
The Special Projects team travels to Romania to search for Hetty, while delving into the history of the Comescu crime family, and their connection to Callen. Hetty confronts Alexa, matriach of the Comescu family, and it is revealed that Callen's grandfather was an OSS agent who killed several members of the family; the Comescus retaliated, killing his mother, but leaving Callen and his sister alive. Meanwhile, Eric and Nell discover that Lauren Hunter, the Office of Special Projects' Operations Manager, is a member of the Comescus. It is ultimately revealed that Hunter assumed the identity of Ilena Vadim - a member of the family who distanced herself from them - to infiltrate the Comescu family; the other members of the team are unaware of her exact allegiance until she kills Alexa and retrieves a laptop from the Comescu beach house. The episode ends in a cliffhanger with the other characters realizing that Hetty has been shot by Alexa. She then collapses to the ground, her fate unknown.
September 27, 2011 9:00 pm
The NCIS team joins forces with the NSA to find the creator and controller of a software program linked to a cyber attack against the Department of Defense. Meanwhile, Callen continues searching for more information about his past.
October 4, 2011 9:00 pm
Special Agent Sam Hanna is sent undercover as a bomb specialist as the team races to locate stolen explosives somewhere in the city. Meanwhile, to much protest, Hunter changes the dynamics of the team and has Callen partnered with Kensi and Sam with Deeks.
October 11, 2011 9:00 pm
The NCIS team delves into the underground world of the Libyan resistance movement following the murder of a news reporter, and Hetty reveals details about Callen’s past.
October 18, 2011 9:00 pm
The LAPD calls upon the NCIS team when a raid links a Mexican drug cartel to a wanted terrorist. Meanwhile, Sam’s most prized possession is stolen.
October 25, 2011 9:00 pm
The NCIS team investigates the murder of a former Navy intelligence officer who had been living a double life and traveling overseas on false passports.
November 1, 2011 9:00 pm
The NCIS team must determine whether a dishonorably discharged Marine is the target of an international set-up or if he committed murder
November 8, 2011 9:00 pm
When a Navy ID is found on a dead body tied to a hazardous material smuggling case, NCIS is granted permission to investigate in Mexico and asked to help locate the missing materials.
November 15, 2011 9:00 pm
After Sam’s undercover mission in Sudan turns deadly, Callen and the NCIS team must track down their missing agent before it is too late.
November 22, 2011 9:00 pm
A botched assignment forces Hetty to fire Deeks and send him back to the LAPD. Meanwhile, an awkward goodbye between Kensi and Deeks leaves her with unexpected emotions for her old partner
December 13, 2011 9:00 pm
The NCIS team must locate a classified device with the power to destroy Los Angeles that was stolen from a college research facility. Meanwhile, Sam tries to track down a highly sought-after Christmas present for his daughter, and Eric meets Nell’s parents.
January 3, 2012 9:00 pm
A new Assistant Director is assigned to oversee LA operations for NCIS, the team begins to wonder what his intentions really are.
January 10, 2012 9:00 pm
When a vehicle transporting Jada Khaled is ambushed, NCIS must track down the culprit to save her and their case. Meanwhile, Sam is forced to confront Jada for the first time since returning from Sudan.
February 7, 2012 9:00 pm
After a diplomatic service van transporting an unknown package from the State Department is hijacked, the NCIS team must determine who committed the crime and what has gone missing. Meanwhile, Callen and Sam celebrate five years as partners, but face one of their biggest challenges when they go undercover for a case.
February 14, 2012 9:00 pm
With Assistant Director Granger critiquing every move, the NCIS team must track down a chameleon-like killer who has evaded law enforcement agents, including their very own Special Agent G. Callen, across several countries.
February 21, 2012 9:00 pm
The team searches for new evidence to prove Kensi Blye’s innocence after she is taken into custody as the lead suspect in a murder investigation involving her deceased father’s sniper unit.
February 28, 2012 9:00 pm
The NCIS: LA team continues to search for new evidence to prove Kensi Blye’s innocence after a private meeting involving her deceased father’s sniper unit turns deadly.
March 20, 2012 9:00 pm
The NCIS: LA team investigates a shooting outside the Vietnamese Consulate just prior to an international conference at the venue that the Secretary of the Navy is scheduled to attend.
March 27, 2012 9:00 pm
When the body of a Navy Intel Officer is found, evidence points to a team of Navy SEALs who are about to depart on a hostage rescue mission, leaving former Navy SEAL Sam Hanna to interrogate the group and possibly compromise the mission.
April 10, 2012 9:00 pm
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.
May 1, 2012 9:00 pm
The joint NCIS: Los Angeles and Hawaii Five-0 task force travel from Hawaii to Los Angeles, when the lead suspect in the case moves to the mainland with a deadly virus in tow. Series crossover part 1 is Hawaii Five-0 (2010) S02E21.
May 8, 2012 9:00 pm
Kensi and Deeks are sent undercover as married couple Melissa and Justin when evidence points to a Russian sleeper cell in a suburban neighborhood.
May 15, 2012 9:00 pm
Callen and the NCIS: LA team confront their vengeful adversary, the Chameleon, when an undercover case ignites a deadly mind game orchestrated by the criminal mastermind.
May 15, 2012 9:00 pm
The L.A. team is drawn into a deadly mind game against a master criminal motivated by Revenge.