Gibbs fights for his life on a Navy hospital ship, while DiNozzo and Joanna go to Shanghai to take down the Calling.
When Gibbs asks the team to help DEA Agent Luis Mitchell with a case, DiNozzo makes a discovery about Gibbs' connection to the agent; Gibbs debuts a new look.
Hours after calling Gibbs about a possible case, a Marine is found dead in Quantico; McGee and Bishop pose as a married couple.
Vance returns to field duty -- with Gibbs as his partner -- when a murder investigation has a connection to a former NCIS agent incarcerated for stealing evidence.
During an investigation, Abby is trapped in a pharmaceutical lab when armed men enter the building and take hostages.
A murder forces Ducky to disclose his participation in a secret society devoted to solving cold cases.
Insurgents in Sudan attack volunteer doctors -- including the man married to DiNozzo's ex-girlfriend, Jeanne Benoit.
A petty officer hoping to prove his innocence volunteers to be court martialed by NCIS if the team investigates his case; Jake and Bishop talk about their marital issues.
A sailor who lost two siblings -- Marines who were killed in the line of duty -- needs a bone marrow transplant; Bishop returns to Oklahoma for Thanksgiving.
Abby's brother becomes the prime suspect when the passengers and crew of a private plane traveling from New Orleans are poisoned.
A seaman who was prepared to testify before a grand jury is murdered, which leads the team to discover the resurgence of an international human trafficking ring; a storm causes power outages all over the city.
An unusual investigation takes place when the body of a murdered deep-sea diver and his suspected co-workers must stay in a decompression chamber for four days.
Secretary of the Navy Sarah Porter's daughter is kidnapped; NCIS Special Agent Valerie Page, McGee's childhood friend, assists the team with advance tactics training.
When Gibbs and McGee travel to Russia to escort a computer engineer home, the mission is compromised and they must hide from a Russian mercenary group that is hunting them.
When a lieutenant is murdered on his way to meet the president, the team must determine if his death was a targeted hit or part of a recent series of muggings.
Ducky and Special Agent Bishop go to London to investigate when a case has a connection to one of Ducky's former friends.
The NCIS team pairs up with the FBI when a research scientist is murdered and the primary suspect is wanted by the Russian government.
A deceased man is spotted overboard during a Coast Guard and NCIS training exercise at sea; Gibbs winds up on a vessel commandeered by pirates.
During a murder investigation, the team uncovers a fraudulent charity targeting those looking for missing military personnel; Tony considers adopting a stray cat that followed him home.
The team investigate a road accident that killed a Petty Officer while Gibbs tries to clear a Navy Hospital Corpsman accused of illegally providing medical aid to the victims of the crash.
Inclement weather keeps DiNozzo, Bishop and her husband at the Dulles airport, where they end up working a case involving an elevated terrorist threat.
The team investigates a series of crime scenes that appear to be copycats of previous cases; two of Gibbs' ex-wives show up at a crime scene.
A rescue mission in Syria reveals evidence that indicates an American was involved in a social worker's capture; DiNozzo's strange behavior is questioned.
An openly gay Navy lieutenant set to receive the Medal of Honor is murdered; Palmer gets ready for fatherhood.
A murdered Marine and alumnus of the military academy DiNozzo attended is found with a student's photograph in his hand; Bishop and her husband ask Gibbs and the team to dinner.
When an explosion rocks a summit on global terror, the team suspects Gibbs' archenemy is responsible; Gibbs tries to help Fornell after his wife's murder.
A murder victim turns out to have been living under an alias created for one of Gibbs' undercover cases from 20 years ago.
The team investigates the world of black market art when evidence in a murder case reveals that a rare painting has been swapped for a fake.
When a dead thief is found in a Marine's home, the NCIS team finds the calling card of a terror group the Department of Defense had been tracking.
A petty officer's murder results in a lead in a 40-year-old airport bombing case; McGee is upset that he was not briefed on the cold case.
When evidence calls for a joint investigation between NCIS and ATF, DiNozzo partners up with his girlfriend, Special Agent Zoé Keates; Anthony DiNozzo Sr. visits.
The team finds a link between a murder in Washington, D.C., and a terror group holding a Marine hostage overseas; DiNozzo is annoyed that McGee was chosen to be featured on recruitment brochures.
When a Navy ensign from the Office of Naval Intelligence is murdered, Special Agent Ned Dorneget (Matt Jones) from NCIS cyber operations helps investigate; Jake and Gibbs' friendship is revealed.
After a deadly bombing overseas, the team pursues a global terrorist group -- and suffers an emotional loss.
When a former NCIS agent's body washes ashore in New Orleans, Gibbs reunites with NCIS Special Agent Dwayne Cassius Pride (Scott Bakula) to determine if the murder was politically motivated or related to a well-known case.
Special Agent Pride (Scott Bakula) and Gibbs follow leads after evidence suggests the Privileged Killer has a copycat; DiNozzo receives a special souvenir from Bishop.
McGee's girlfriend, Delilah, turns to the team for help when she finds a break in a controversial case; McGee considers asking Delilah to move in.
A Marine photographer goes missing before providing testimony in a highly publicized case; Abby helps a young homeless woman.
DiNozzo is sent to Paris to bring an Admiral's daughter home, but he needs help from the team after encountering a controversial crime scene.
The team investigates a fire on a U.S. Navy ship that was a secret detention site for indicted terrorists; Gibbs goes to his childhood home after his father's passing.
Tony helps Ziva and her mentor look for a missing Marine lieutenant in Colombia; Jimmy Palmer chooses his best man.
The team works with the Baltimore police to investigate a warehouse fire that revealed missing Navy documents that could potentially threaten national security; Tony reunites with a boy from his past.
An investigation into a fire on a Navy vessel leads to a discovery that elevates security at Navy facilities worldwide; Ziva and DiNozzo are called in when an explosive device is found on a ship in Italy.
As the team searches for a terrorist targeting the Navy, a bug is found in a probationary agent's tooth; Jimmy Palmer has a bachelor party.
When the dead body of arms dealer La Grenouille is discovered, the FBI investigates the NCIS team, and Jenny Shepard becomes the prime suspect.
Two members of the team are sent to Iraq when a mortar attack in Baghdad turns into a murder.
When a Marine's wife kills the intruder who tried to rape her, Gibbs and his team realize they are tracking a serial rapist and killer who uses a racy Web site to stalk his prey.
Tony goes under cover as an escaped prisoner chained to a convict who holds the key to recovering stolen Iraqi art, but when his GPS device fails, the team must find other ways to locate him.
Gibbs and the NCIS team work with a notorious private detective during an investigation of a naval officer found murdered at the bottom of a lake.
The team investigates a telemarketer's report of the murder of a petty officer after hearing it over the phone, and it appears to be a hoax until the body of the officer is found.
When bodies found stuffed in a barrel are identified as a prosecutor and a sheriff who worked on a rape and murder case with Ducky 10 years ago, Gibbs believes Ducky may be the next target.