After a Navy officer dies on board Air Force One and a Marine dies simultaneously on the ground, the NCIS uncovers a possible hit on the president.
When a mishap during a training jump leaves a Marine dead after his parachute refuses to open, the NCIS suspects that it might not be an accident after all.
Gibbs becomes determined to prove the innocence of the late Navy officer Seadog after the circumstances of his death implicate him in a drug deal.
Kate goes to bat for a drowned sailor whose death is suspected to be a suicide. As the team looks into the incident, they uncover a plot that threatens to destroy a US destroyer.
When the remains of a Navy officer who was thought to have stolen government funds are found, the team works tirelessly to get to the bottom of what happened and identify the real culprit.
When two sailors exhibit signs of an overdose despite claiming to be clean, the team soon comes to notice that something is wrong with the entire crew of the USS Enterprise.
The discovery of a partially composed body reveals a case of identity theft and the presence of a mole on board a submarine.
When a translator from Gitmo dies from the presence of emeralds in his stomach, the team races to discover the source of the emeralds and if they have something to do with a prisoner linked to Osama Bin Laden.
A call from a supposedly dead Marine sends the NCIS on the tail of a rogue CIA agent who is involved in a deadly cover-up of a failed mission.
The team races to prevent a disaster after an amnesiac woman claims that there is a bomb on an unidentified ship, sending them on a desperate quest to identify the ship before it's too late.
When a Navy diver is killed while testing a secret device, the investigation leads Gibbs to suspect that the murder had nothing to do with the diver's work.
When the severed limb of a Marine is found, the team is shocked to discover that the person that the severed limb belongs to had died two years before.
The death of two Marine recruiters causes the NCIS to team up with the FBI in order to catch the vengeful sniper who is responsible for the murders.
As several execution-style murders happen back-to-back, the team scrambles to identify the connection between the victims and who might want them dead.
Gibbs risks his career to help his former CO prove his innocence after he is accused of stealing 2 million dollars during an ambush in Iraq.
When a gunman takes part of the team hostage, Gibbs and Tony enlist the help of the FBI to save their comrades.
The death of a petty officer sends Gibbs on the tail of his co-workers who appear too collected and consistent for his taste.
When a convicted murderer breaks out of prison, the team casts doubt upon his conviction when he appears to be methodically following the trail of the real murderer.
When one of their own is brutally murdered, the team resolves to solve the cold case that he was investigating in order to find his killer.
A missing person case leads the team to uncover a wider conspiracy that threatens the lives of the marines of the same unit.
The investigation into the death of a marine sends the team into the depth of a black market for weapons.
The team faces pressure to conclude the investigation into the suspicious death of a Navy SEAL in order for a sensitive hostage rescue operation to go through.
Gibbs' determination to find the gunman who had taken his team hostage before reaches new heights when the gunman strikes again, leaving the life of one of the team members hanging on the line.