Aboard Air Force One a Navy officer dies after eating with POTUS, then a Marine officer who is connected with AF1 also dies in the same way while in Georgetown. Abby identifies the cause, but does Gibbs have time to save the president?
During a training jump, a Marine dies when his main chute fails to open and he fails to pull his reserve chute. Kate joins the NCIS team, and together they investigate the method of the murder to find the perpetrator.
A US Navy commander nicknamed "Seadog" washes up dead on a North Virginia beach. Two dead alleged drug dealers are found nearby. All three victims are shot. NCIS, joined by DEA and FBI, investigate.
A swimmer finds the weighted body of a seaman who has disappeared from a US Navy destroyer. The NCIS team investigates a petty officer connected with the victim, but a plot against the skipper is uncovered.
A hunter finds an aircraft cargo pod containing a mummified Navy disbursing officer who disappeared from his aircraft carrier, as did 1.2 million dollars. The NCIS team investigate to see if there are old injustices to be righted.
During a port visit by USS Enterprise, a chef finds a naked sailor inside a restaurant freezer in Spain. Later at sea, while NCIS investigates, another sailor freaks out on the flight deck. After that, one of the two mysteriously dies.
Workers find the decomposing body of a man, apparently a submariner, inside a drum of acid. The team treats the case as both murder and identity theft. Gibbs and Kate go aboard a sub at sea, hoping to find the killer and save the crew.
A naturalized petty officer of Egyptian descent dies in the US from massive bleeding due to an intestinal blockage caused by emeralds; he had just arrived from Camp Delta at Gitmo. To prevent another murder, the team investigates at Gitmo.
Two Marine majors supposedly die during a classified operation in an undisclosed foreign country; one of them purports to call home. The team investigates.
A woman claws her way out of a shallow grave. She has no memory of her past, but she is certain that there is a bomb about to go off on a US Navy ship. While the rest of the team seeks the bomb, Kate tries to help her recover her memory.
A SEAL officer, a diver, dies of a stab wound after swimming while testing a classified handheld sonar device, which disappears. An anonymous caller reports the murder. Gibbs and the gang search for the murderer and the device.
A dumpster diver finds a severed leg, apparently from a Marine, believed to be attached to a live person not more than 24 hours earlier; however, the Marine in question, according to records, died two years previously.
A Marine recruiter dies in his office from a single shot. Gibbs and the gang investigate, then a second one dies in the same manner. The Gibbs group expect a third murder, so they set a trap.
A Navy dentist from a naval air station dies of a single shot to his back, apparently in an execution-style murder. Two more men from the same station soon die identically.
A Marine colonel disappears during an ambush in Iraq, as does $2M in cash; he re-enters the US under an assumed name; the FBI seeks him, and so does Gibbs, with whom he served while on active duty. Gibbs finds him.
A foreign agent enters the autopsy room via an unconventional method; he then takes captive Ducky, Gerald, and, later, Kate. He demands evidence pertaining to a body in the room. He eventually asks to see Gibbs, who obliges him.
The body of a petty officer falls from a ceiling at a nightclub; Ducky says that someone dressed him after he died. Gibbs finds $40K in the victim's room, and the team follows the money through twists and turns, hoping to find his killer.
A prisoner, who was a SEAL petty officer, escapes from Fort Leavenworth while serving time for having killed his wife and a cable guy. The team, seeking to determine where he may go next, consider whether his conviction was wrong.
A guard finds the disemboweled body of an NCIS agent in an elevator; the gang investigate. Gibbs feels responsibility. The victim has pursued a cold case involving a theft of $12M+ from the Navy.
Teenagers at play find the body of a Marine impaled on a post. The victim was an armorer at Quantico. Gibbs and the gang investigate both the murder and the theft of surplus weapons. An ATF agent takes an unusual part.
A SEAL lieutenant falls to his death, due to a failed fitting in his gear, while rappelling during an exercise; Gibbs and company investigate; the CIA expresses intense interest. Abby and McGee provide answers, and the team solve the case.
With extreme determination Gibbs continues, to the extent of obsession, to concentrate on the unknown terrorist who shot him and escaped. The bad guy reappears, but Kate and Tony disappear temporarily. Gibbs eventually meets his quarry.