An experimental Naval aircraft crashes on Oahu, and Tennant and her team must find who is behind it before classified state secrets are exposed.
Tennant and NCIS must take down a notorious team of international thieves using WWII explosives on armored trucks before they complete their final big job and disappear. Also, Kai searches for a new place to live; Lucy and Whistler have a standoff about their previous encounter; and Ernie’s mission in the field is more alarming than he expected.
Kai goes undercover with one of Hawai`i’s oldest surf gangs when a petty officer who’s trying to help wayward kids find a new path in the Marines is murdered.
When a beloved Paniolo (Hawaiian cowboy) is shot while out riding his horse, Jane and her team must gain the trust of the Paniolo community to help find the culprits and protect the Paniolo's life. Also, Kai tries to convince his stubborn father to see a doctor.
When a Japanese sailor is killed on American soil and evidence links the case to the previous murder of the victim’s girlfriend back in Japan, NCIS must find the murderer before the wrong person is accused and the case triggers a diplomatic crisis. Also, Captain Milius makes a personal request to Tennant.
When Tennant and NCIS are tasked with finding a kidnapped globe-trotting social media star, they find that she is not who her husband, or her followers, think she is. Also, the team is at odds with Whistler, who has an agenda of her own.
When a Navy petty officer is murdered, Jane and the team investigate while protecting the victim’s friend and colleague.
When an anti-capitalist protestor is murdered, Jane and the team investigate and find themselves caught in a war between eco-activists and a tech billionaire fighting over a piece of land. Also, Jane and Captain Joe go on a date.
The NCIS team investigates a cold case involving WWII-era bones on the 80th anniversary of the Pearl Harbor bombings, and are shocked to learn they belong to a 100-year-old survivor of the attack.
NCIS crosses paths with Whistler’s team while investigating a shipping container filled with contraband weapons. Also, Tennant debates arresting Alex’s friend’s dad, knowing it will cause her friend to move away.
When evidence to put away a drug kingpin is stolen, Lucy goes undercover at an underground poker tournament to find out which high-roller is behind the crime. Also, Lucy’s feelings are in turmoil when Whistler’s ex-girlfriend arrives in town.
When NCIS investigates the mysterious death of a Navy engineer, Joseph Chan, they learn the last person he met with was his colleague, Maggie Shaw, Jane’s mentor and friend, who’s been kidnapped. Also, David Sola, a New Zealand intelligence service case officer arrives in Hawai’i, following a lead in his case that connects Joseph’s death to a Chinese black op secret agent.
While Jane investigates Maggie’s kidnapping, she’s shocked when she learns the truth and enlists her team and Whistler to prove her findings.
While Jane is questioned following Maggie Shaw’s arrest, the rest of the team investigates a mysterious case of Marines with damaged ear canals from a weapon that emits ultrasonic waves. Also, Ernie visits his friend, Dr. Tony Lee, to identify possible suspects who had access to his classified weapon.
As Jesse enjoys a day sailing with his daughter, Gracie, pirates suddenly seize their yacht, take all the passengers hostage and attack Jesse, leaving it up to his team to quickly locate and rescue his daughter.
Kai goes undercover as a chef in a local restaurant to gather intel on a notorious criminal kingpin who has a connection to the eatery. Also, Jane discovers that a school on the mainland has recruited Alex on a baseball scholarship, which he’s kept secret from his family.
When a ransomware attempt causes a dam to malfunction, Ernie and a team of hackers are tasked to find the culprit quickly, before all power and water is cut off on the island. Also, Lucy and Whistler work together, giving Whistler a chance to apologize to Lucy and mend their relationship.
NCIS Agents Nick Torres and Jessica Knight travel to Hawai’i when they learn a key witness in one of their old cases has turned up there with crucial evidence.
The NCIS team investigates a shipwreck carrying exotic animals that now threaten the native wildlife on Oahu. Also, Alex sustains a career-ending injury and Kai asks Melanie, a fish and wildlife agent, out on a date.
When a navy seaman is involved in a murder, the NCIS team is called to work the case on their day off. Also, Lucy finds out Whistler turned down a promotion in D.C. to stay in Hawai’i.
Captain Milius returns to Hawai’i for a secret prisoner exchange operation, and brings in Jane to be his personal security escort in the Philippines, where the exchange will take place.
Captain Milius continues to work with Tennant and her team in the aftermath of the prisoner exchange between U.S. and eastern Europe. Also, Whistler takes Ernie’s advice and makes a grand gesture in the hope of winning back Lucy.
Special Agent Tennant’s team, along with NCIS agents Nick Torres and Jessica Knight, learns about plans for an attack on RIMPAC (The Rim of the Pacific Exercises) in Oahu, the world’s largest international maritime warfare exercise.
The NCIS team’s investigation takes them deep into the world of illegal street racing after a Marine staff sergeant’s body is discovered in a junkyard. Also, Tennant is concerned Alex is hiding something from her, and Whistler is anxious about introducing Lucy to her co-workers.
Tennant and the NCIS team suspect foul play when they investigate a fatal car crash involving a Navy officer who turns out to be an imposter. Also, Whistler finds herself in danger when she goes undercover to learn the truth behind the accident.
When a Navy sailor washes up dead in a sacred, forbidden kapu site, the NCIS team brings CGIS Special Agent Pike to unmask the mystery and catch a possible serial killer on the island. Also, Tennant meets Alex’s new girlfriend.
The NCIS team investigates the death of a Navy sailor and goes head-to-head with a ruthless local criminal organization. Also, Lucy looks for a new apartment.
When a Marine Corporal dies in a tide pool after being exposed to fentanyl, the NCIS team must quickly find the source of the drugs. Also, Alex talks to his parents about taking a gap year and Ernie reveals personal news to Lucy.
When the mother of a young boy goes missing, the NCIS team sets out to find her and learns they aren’t the only ones searching for her.
When a naval officer is murdered while moonlighting in community theater, the NCIS team recruits a familiar face to help lead them to a ruthless international killer. Also, Kai enlists Whistler to open an investigation into an old friend turned criminal.
When Commander Chase is abducted from her home by an Army Ranger accused of murder, the NCIS team must act quickly to find her and the suspect.
Tennant, Jimmy Palmer and Sam Hanna find themselves captured with a woman who claims to be a CIA agent demanding intel from the team. Also, Jesse, Ernie, Whistler and Alden Parker learn about an asset that arrived in Hawai’i who could be connected to several overseas assassinations.
When Special Agent Pike is ambushed while working undercover with a local Japanese crime family, the team must find the person responsible for orchestrating the attacks. Also, Kai goes deeper into his investigation regarding an old friend turned criminal.
When an elite special forces Marine captain is murdered, the NCIS team finds a suspect in a really unusual place.
Following a close call at a meth lab explosion, the NCIS team learns Kai is being targeted by his old friend-turned-criminal and must take him down. Meanwhile, Lucy gets her first big case aboard her aircraft carrier.
When the murder of a captain and his wife echoes a previous case, the NCIS team brings in a former team member to help determine if they are dealing with a copycat killer.
When a Navy deserter accidentally comes out of hiding, his family becomes a target that drives the NCIS team and Charlie 1 to investigate who is after them. Meanwhile, Lucy surprises the team by returning to Hawai'i from her agent afloat job early.
When Navy residents discover their vehicles were burglarized overnight, the NCIS team connects it to a series of peculiar crimes and tracks down an unlikely bandit. Also, Whistler struggles with an uncooperative CI and Alex weighs his college options.
Captain Milius returns to Hawai’i as the NCIS team works to catch a dangerous high-value U.S. Government target with the help of an informant unlike any they’ve ever encountered. Also, Tennant and Daniel deal with Alex’s acceptance into the Naval Academy.
When Tennant interrogates a suspect during his helicopter transfer and the helicopter crashes, she must utilize her skills to save herself and the other passengers.
After the mysterious death of an astronaut in a highly sensitive Mars simulation, the NCIS team must send Ernie into the habitat to investigate alone.
When Lucy receives a strange call on night watch from a man admitting to murder, the NCIS team sets out to find him.
The discovery of a dead former MI6 agent uncovers secrets from Tennant's past, forcing her to go to extreme lengths to track down the responsible party.
When a figure from Tennant's CIA past re-emerges, the NCIS team seeks help from the most unlikely place to catch a killer who threatens to destroy everything Tennant has built.
