The death of an American seaman on a U.S. nuclear submarine during an AUKUS ceremony on Sydney Harbour is investigated in a joint effort between America's NCIS agents afloat and the Australian Federal Police.

When a Navy compliance officer is found dead in a waterhole from a snakebite, the team works to uncover the origin of the rare deadly taipan that is uncommon to the area where the officer was discovered.

When a shark spits out an arm wearing U.S. Navy equipment, the team's investigation tests the loyalty of a band of former Navy divers.

When a U.S. petty officer's body is found in Sydney's historic and haunted Rocks area, a decades-old Navy Cross medal holds the clue to solving the murder, leading the team on a wild ghost chase to catch a killer.

The team races to save one of their own when Doc Roy and his dog are involved in a hostage situation at their local dog cafe.

When the suspicious death of an old Drug Squad colleague pulls Evie back into a secret undercover operation, DeShawn is torn between loyalty to his friend and loyalty to his team.

A glitzy tech launch turns into a disaster, leaving half of NCIS: Sydney trapped underground, and the others scrambling to save the day before the clock and the oxygen runs out.

When JD's son is kidnapped by an international assassin in exchange for a wanted criminal in NCIS custody, the team frantically tries to get his son back safely without trading in a criminal.

NCIS: Sydney will do whatever it takes to crack the case of a rogue assassin on the run during NCIS Special Agent DeShawn Jackson's chaotic first day as boss.

When a young girl finds the body of a former U.S. Navy officer floating in the harbor, the team is led to an 18th-century sailing ship hosting a pirate-themed wedding, where DeShawn and Evie go undercover to investigate. Meanwhile, Mackey and JD are pulled in to prevent a potential tragedy on the harbor that could rip the U.S.-Australia alliance apart.

When the body of a long-missing U.S. Naval engineer is discovered buried in concrete, the team enlists Doc Roy's old friend to assist in the investigation.

The team is thrown into the murky world of online conspiracies after a car owned by a U.S. Navy cyber engineer explodes just as her teenage daughter was about to take a driving lesson.

When a petty officer is found murdered and frozen, it leads the team into a twisted underworld of seafood and sex trafficking.

The suspected suicide of a former U.S. Navy SEAL leads NCIS: Sydney to a wellness retreat to investigate a group of his fellow former SEAL buddies.

The suspicious death of a US Navy chorister draws NCIS: Sydney into the world of obsessive fans, pop stars, and earworms, as they learn how deadly the music business can be.

The discovery of an exsanguinated sailor takes NCIS: Sydney into the world of modern-day vampires, family feuds, bespoke vodka and a nocturnal matriarch with a penchant for blood.

The team battles searing temperatures to investigate the death of a U.S. Marine corporal killed during a joint training exercise between U.S. and Australian troops.

With a Stinger missile and murderer in the wind, and Darwin's World War II Commemoration ceremony fast approaching, NCIS: Sydney races to prevent a deadly attack.

The discovery of two missing U.S. Navy aviators adrift in the Coral Sea leads the team to expose a sinister terrorist plot.

Growing increasingly worried about Blue’s strange behavior, Doc takes matters into his own hands and breaks into her apartment. Inside, DeShawn and Evie stumble onto a startling revelation that forces the team to question just how well they really know one of their own.

The team’s hunt for a high-value U.S. target accused of murdering an Australian soldier takes an unexpected turn when the suspect claims to have evidence of a war crime.

A U.S. Navy pilot goes missing at a UFO hotspot in the Outback after being chased by bright lights.

When a U.S. Navy attaché is found dead with a USB lodged in his throat, the team tracks a killer believed to have ties to an international chess tournament in Sydney.

Confronted with Australia’s first case of Ebola, the team races to uncover how patient zero, a U.S. Navy scientist, contracted the deadly virus, only to have their search for answers complicated by a top-secret military research agency as two of their own fight for their lives.

When a U.S. naval officer is arrested for murder while trying to destroy a treasure map, the team must navigate jurisdictional politics to uncover the truth while racing to find the fabled “Yamashita’s Gold".

When an American sailor accused of murder is shot dead, the team discovers he was the subject of a popular true-crime podcast and investigates whether a superfan took justice into their own hands.

The team races to an Antarctica research base to investigate why a climate scientist killed a colleague on Polar Night Eve – and make it out before their plane engine freezes and they’re trapped in darkness for six months.