Gibbs returns to his childhood home following news of his father's death, while the team look into a fire on a US Navy ship that served as a secret terrorist detention site.
DiNozzo is sent to Paris on a covert mission to escort an Admiral's daughter home, but turns to the team for help when he comes upon a controversial crime scene.
The NCIS team searches for a Marine photographer who went missing just before he was due to testify in an Army court-martial hearing. Abby tries to help a young homeless woman.
After a Navy officer is found dead, the team must ascertain if the murder was the result of a bar fight or because he knew too much about an attack on a fellow female officer.
After returning to her job at the Department of Defense, McGee's girlfriend Delilah finds a break in a controversial case, prompting her to turn to the NCIS team for help.
When the body of Congressman Dan McLane washes ashore in New Orleans, Gibbs reunites with former colleague Dwayne Cassius Pride in a joint case between them and the FBI.
After a bomb detonates in a dressing room at a military charity concert, the team must determine if the target was a washed-up '80s rocker or if it was part of a larger scheme.
When DiNozzo confronts a man impersonating a Navy officer, guns are drawn and the perpetrator is left dead. The investigation uncovers that the only eyewitness is DiNozzo's father.
After uncovering faulty bulletproof vests in a stolen truck, the team attempts to locate both the source and any vests that had been shipped to military personnel.
When a stolen drone is linked to the elusive terrorist Parsa, the team partners with the Department of Defense to track down the device before it is used for a large scale attack.
After an illness strikes children from military families, Gibbs investigates. Abby and Jimmy partner with the Naval Medical Research Center to determine the strain of illness.
After discovering the Secretary of the Navy was bugged during a confidential briefing, NSA Analyst Eleanor Bishop partners with the NCIS team on the case.
The NCIS team is forced to re-examine a hit-and-run murder case when a former FBI agent turned lawyer confides in Gibbs that her client's confidential alibi is solid.
After Gibbs leaves mid-case to help his father reconnect with a former war pilot, Tony and McGee argue over who should lead the murder investigation of a Marine Sergeant.
NCIS partners with the Coast Guard Investigative Service to investigate an explosion on an oil rig. Meanwhile, no one is safe from a prankster who is targeting the NCIS team.
DiNozzo returns to his Baltimore Police Department days when he sees a felony suspect from a 15-year-old case at the NCIS crime scene of a murdered Petty Officer.
The NCIS team must rely on Twitter for a case involving a missing Navy Lieutenant. Meanwhile, McGee misplaces his badge but withholds the information from the authorities.
Determined to locate Ziva, Tony chases leads in Israel in search of her whereabouts. Meanwhile, Gibbs and the team continue the hunt for Parsa and his growing terrorist ring.
A petty officer chases and attacks a man in the street, later asking to speak with someone at the NCIS to explain himself. The DoD takes an interest in the case.
Tony and Ziva return to work, and the team locates the getaway car and the body of the wheelman. Armed with an important new clue, they seek to bring an end to the madness.
Tensions rise between the NCIS and Mossad when the later group misuses NCIS assets under the orders of their new director Orli. Tony and Ziva have a run-in with an SUV.
The team is called in to investigate when a Navy lieutenant returns home from a tour to discover that her husband has gone missing, and her home has been left in a mess.
A ship's medical officer is murdered while his destroyer passes through a storm at sea. Gibbs and the team head out to investigate, and discover McGee's admiral father is on board.
A Marine is shot dead while on patrol in Afghanistan, hit by a single bullet thought to have been fired by a Taliban sniper. The man's widow has good reason to suspect otherwise.
Gibbs and the team set up an unusual trap to capture the one of the most prolific and accomplished cyberterrorists in the world. Tony and Ziva have a run-in with Ebola.
The body of a Marine and a young woman are discovered by members of the public in a wrecked car. The team investigates, and Ducky asks some difficult questions.
The team continues the investigation into the killings at Vance's home, and before long the uncover the identity of the man hired for the job. But who hired him?
The team is sent to investigate the murder of a Navy officer, and their efforts lead Gibbs to believe a former close friend of his father's may be involved.
A Navy helo goes missing, and three survivors wash ashore in an inflatable raft. Gibbs and the team are joined by a member of the CGCIS for the investigation.
Ducky unofficially calls for the exhumation of a body whose autopsy he conducted 12 years previously, claiming he now has reason to suspect the person was murdered.
Abby is still having nightmares, and a psychiatrist is hired to perform mandatory evaluations on all hands. The body of an armoury worker is found four months after the explosion.
After the attack on NCIS, the President orders all agencies to pursue Harper Dearing with "extreme prejudice". Meanwhile, Ducky tries to recover from his heart attack.
Dearing gets a surprise from a dentist; Gibbs and company continue to investigate Dearing and the thermite incidents. Amid the madness, Vance disappears.
A fire in a warehouse in Baltimore brings in the NCIS; while Gibbs and company investigate the fire and a death, they find connections to the Phantom Eight.
Gibbs and company investigate when a boatswain's mate second-class dies of a stab wound while on liberty in Baltimore. Vance discovers that he is too close to the case for comfort.
When a shooting occurs at a seminar on Gibbs' and Tony's watch, Gibbs must work together with both Secretary of the Navy and Dr. Samantha Ryan to find out what happened.
Top-secret clearance from a Naval research laboratory is jeopardised when the murder of a Chief Petty Officer is connected to an international arms dealer.