The NCIS team partners with the State Department after the murder of an arms dealer is connected to a series of crimes seemingly executed by someone with elite special forces training. Also, Callen visits ATF Agent Anna Kolcheck in prison as she awaits her sentencing.

Sam assists a Department of Justice agent with locating a former U.S. boarder patrol officer who disappeared after the cartel threatened him; Kensi partners with a special agent from the Criminal Investigative Department to recover a stolen hard drive with sensitive military information.

Faced with multiple cases worldwide, the NCIS team splits up, with Callen and Sam working with Mossad Agent Eliana Sapir in Tel Aviv, and Kensi partnering with DOJ Agent Lance Hamilton in Los Angeles.

When an FBI agent is killed while trying to track the location of an undercover agent, NCIS must find the missing agent before the criminals he was investigating do

When DOJ Agent Lance Hamilton's partner is killed, Sam dons his previous undercover persona of "Switch" to find the culprit. Also, Kensi, Deeks, Rountree and Kilbride work to catch an aerospace engineer who stole classified Navy schematics.

When Sam's friend Tom Olsen finds himself being hunted down by enemies from his past, the NCIS team must find out who is after him.