Deeks is arrested and interrogated in connection with the murder of his former partner, while the team tries to prove his innocence.

The mole has once again compromised the NCIS team as planted evidence results in the arrests of Callen, Sam, Granger and Deeks, on the day Under Secretary Duggan (Jackson Hurst) returns for Hetty’s resignation.

Hetty goes rogue, leaving the NCIS team completely in the dark, and the mole kidnaps one of the agents.

A gold heist investigation has the NCIS team working with Hetty's former Vietnam War colleagues, Retired Admiral AJ Chegwidden, Admiral Sterling Bridges and Retired Captain Charles Langston.

LAPD Detective Whiting calls in a favor when Deeks' former partner goes rogue.

While assisting NCIS with an undercover operation, informant Elizabeth Williams is arrested and the team is unable to provide her with an alibi. Also, Callen meets with ATF Agent Anna Kolcheck who remains on suspension following her last joint case.

Rountree and his younger sister are pulled over by police and treated harshly in a clear case of racial profiling. Also, NCIS investigates the death of a Navy photographer who was assigned to document the building of a new weapons station.

Sam Hanna must go undercover as a fighter to catch the leader of a gang dealing drugs on the streets