Secrets arise when Gibbs former mother-in-law surfaces as a witness in a murder investigation.

While investigating the suicide of a retired Navy officer who left a rare, valuable – and possibly stolen – coin to the National Museum of the Navy, the team imagines…

Director Vance is notified by the Pentagon that the nuclear submarine Gibbs and Bishop are aboard to conduct a murder investigation has gone radio silent.

After a mural by a street artist and activist is stolen, the NCIS investigation leads to a conspiracy regarding a Navy contractor and the safety of ocean mammals. Also, Bishop…

While they’re in Russia, Callen, Sam and Anna craft a plan to break Anna’s father and his CIA agent companion out of prison. Also, Special Agent G. Callen finally learns…