The team learns that someone from their past is targeting one of their own. Nate Getz attempts to help Nell get through a traumatic experience.

Gravely injured and unable to communicate with the team in the U.S., Callen, Sam and Kensi, with an unconscious Deeks in tow, search for a safe way home as a cartel boss places a “dead or alive” bounty on their heads. Also, Mosely and retired Navy Admiral Hollace Kilbride beseech their contacts in Mexico and D.C. for assistance with their missing colleagues

After the prototype for a tactical assault suit is stolen from a Navy base and used in a Beverly Hills jewelry heist, the team must determine who stole the suit and what their next target is. Also, retired Navy Admiral Hollace Kilbride temporarily oversees the team while Mosely and Hetty face repercussions for the unsanctioned Mexico mission.

The NCIS team is in danger after their pictures, as well as Mosley and her son’s names, are included on a cartel hit list. Also, NCIS Deputy Director Louis Ochoa arrives with Special Prosecutor John Rogers to interview Mosley about the off-the-books mission in Mexico.

Callen and Sam run protection detail for retired Navy Admiral Kilbride in an operation to locate a missing Naval intelligence officer.

While NCIS must track down an organized crime leader who is trying to buy stolen defense technology, Callen goes to Anna to ask the ultimate question. Also, Deeks is kicked out of NCIS training only to find that Hetty has a life-changing surprise for him.

When Callen goes to the National Counterterrorism Center on the pretext of interrogating a Russian asset from the crashed plane case he investigated months earlier, the tables are turned and he is detained, accused of being a Russian agent.

Callen and the team discover that Anna is being held by a group with ties to Anna's upbring and must rescue her before she is forcibly returned to Russia. Also, Admiral Kilbride makes Nell a serious offer.

When military grade technology is stolen, a deaf engineer, Sienna Marchione, who always wanted to serve her country, and the only member of her team to survive the theft, helps Kensi and NCIS track down the tech before it’s taken out of the country.

When a Naval Intelligence Officer is tortured and murdered, NCIS must work with Joelle, who informs them that other CIA operatives are being killed in the same way. Also, Kensi receives a threatening postcard from David Kessler, the sociopath who is obsessed with her.

Deeks is kidnapped by an associate of Kirkin’s in need of his help and NCIS investigates the shooting of a militarized dolphin equipped with a Russian microchip. Also, Beale makes Nell an interesting offer and Hetty returns.

While Callen suspects Hetty of keeping secrets about his past and Joelle surfaces in her quest to capture Katya, NCIS must track down an informant whose life is in danger. Also, Kensi and Deeks work to expand their family.

NCIS takes the case personally when an LAPD officer’s father, a beloved elderly Japanese American veteran, is the victim of a vicious hate crime.

Sam and Kilbride clash when a case involving an arms dealer responsible for the slaughter of ATF agents leads them to a well-connected colonel and friend of Kilbride, accused of supplying militia groups with guns. Also, Kensi and Fatima go undercover at a rehab facility to question the arms dealer’s girlfriend.

As Callen continues hunting Katya, Kilbride enlists NCIS to help find a truckload of stolen guns. The assignment becomes more challenging when their suspect, the son of a mob boss they believe was planning to sell them, is found dead.

When an NCIS mission to protect a compromised undercover agent goes completely sideways, the agents are individually interrogated to find out what really happened. Also, Kilbride must make a difficult decision.

Sam negotiates and Rountree goes undercover, when a man takes a busload of hostages and threatens to blow it up unless his daughter’s war crimes are posthumously cleared.

NCIS investigates the apparent suicide of a Navy intelligence officer who leapt to his death after taking LSD. Also, while Kensi is away, Deeks makes plans to redo the backyard without her input.

The NCIS team scrambles to find Kensi, when she is attacked and kidnapped by a mysterious militia group while helping a group of migrants cross the border.

The NCIS team helps a U.S. ambassador search for her missing daughter, Gia, a popular social media influencer. Also, Agent Aliyah De León returns to support the team with the case.

When a civilian scientist working with the marines is killed, and her advanced radar technology stolen, the NCIS team must scramble to find the missing technology and the culprit. Deeks worries about how to tell Callen that he's selling the bar.

When a newborn child is found abandoned on a Navy ship, Kensi and Deeks search for the mother on board before she dies of complications. Also, Nate meets with Admiral Kilbride and learns about the CIA project from the ‘70s and ‘80s involving children.

The NCIS team investigates an unidentified aircraft that flies into U.S. airspace and crashes into a Navy plane. Also, Deeks and Kensi begin to prepare for their foster inspection.

When DOJ Agent Lance Hamilton's partner is killed, Sam dons his previous undercover persona of "Switch" to find the culprit. Also, Kensi, Deeks, Rountree and Kilbride work to catch an aerospace engineer who stole classified Navy schematics.

NCIS investigates the robbery of a high-end arts storage by going undercover as potential buyers on the black market, to find who is behind the stolen items.

Rountree and his younger sister are pulled over by police and treated harshly in a clear case of racial profiling. Also, NCIS investigates the death of a Navy photographer who was assigned to document the building of a new weapons station.

NCIS investigates the kidnapping of Master Sergeant Boomer, a military working dog. Also, Sam looks to sell his boat so he can take care of his father who is suffering from Alzheimer's.

The NCIS team helps Naval intelligence officer Akhil Ali locate a fellow officer who went missing while recruiting foreign assets as potential sources of intelligence. Also, Callen and psychologist Nate Getz track down a man Callen believes was present for his training when he was young.

NCIS investigates the murder of a woman employed in the Navy’s missile defense program and its connection to stolen Navy missile technology. Also, a strict social worker stresses out Deeks, and Sam debates selling his boat.

The NCIS team works with DEA Agent Talia Del Campo to find a missing whistleblower set to testify against gun manufacturers marketing to drug cartels.

NCIS investigates after two men are blown up by their own explosives while attempting to break into a military base. Also, Callen wants to take the next step with Anna, and Sam moves in with his father, Raymond.

The NCIS team must quickly find Callen after he falls for Katya’s trap using Sam’s deepfake to coordinate a weapons deal.

The NCIS team hunts for a heist crew that robs a Los Angeles casino with military-grade power. Also, Kensi and Deeks hear exciting news regarding the adoption and Callen takes a big step in his relationship with Anna.

The NCIS team searches for a suspect and their motive following the bombing of a large facility where military combat drones are assembled. Also, Callen and Kilbride get troubling news about a body found in Syria.

After an architect duo who specializes in designing secure buildings is kidnapped, the NCIS team mounts a search to bring them home. Also, Deeks and Kensi realize they may need to get Rosa some help with her schoolwork, and Anna considers a career outside of law enforcement.

The NCIS team join forces with the FBI when a group of grisly murderers known as “The Body Stitchers” returns after evading capture by NCIS years ago. Also, Sam’s dad makes a new friend in Arkady.

When Aiden Hanna's plane crashes and he is accused of being at fault for the accident, the NCIS team must investigate to clear his name; Rountree considers how he wants to handle the aftermath of the incident with the LAPD.

NCIS is called to investigate when a woman is seen fleeing the scene of her husband's murder. Also, Roberta Deeks comes into town to meet Rosa, and Sam looks for another aide for his father.

NCIS is called to investigate after Rear Admiral Ted Gordon is abducted from his home. Also, Kensi struggles with being the fun parent while Deeks is apartment hunting with his mom.

When a Marine falls ill during a training mission due to an attack by a genetic weapon, the NCIS must track down the person responsible for unleashing it. Also, Deeks struggles with balancing work and home life when Rosa comes down with the flu.

NCIS investigates an arson attack at Global West Ventures Corp, a naval defense contractor. Also, Rountree connects with an ex and Kilbride gives Callen files on Pembrook.

When NCIS investigates a shootout on a boat in which a rare cultural artifact is stolen, they’re shocked to learn who owns the boat.

While Agent Rountree and Fatima are searching for Kilbride, who has been MIA, they are ambushed and learn that every member of the team has a $200,000 bounty on their head via the dark web. The NCIS team must save Agent Rountree and find Kilbride while every cartel, hit man, gang and psychopath hunts them down.

The crossover starts on NCIS S20E10 Too Many Cooks (I) and NCIS: Hawai'i S02E10 Deep Fake (II).

When Sam's friend Tom Olsen finds himself being hunted down by enemies from his past, the NCIS team must find out who is after him.

The NCIS team must quickly find Kensi and Fatima after they are kidnapped and drugged while searching for a missing Navy lieutenant who they learn has ties to a dangerous Islamic militia.

When a mystery woman attacks the founder of an AI company, the NCIS team must identify the woman before the next major global conflict ensues. Also, Kilbride's ex-wife, Elizabeth, comes to visit and asks him to think about reconnecting with their son.

When a petty officer is found dead with an apparent suicide note, the NCIS team must investigate the mystery surrounding his death. Also, Callen and Anna begin wedding planning and Sam has a heart to heart with his daughter.

Sam Hanna must go undercover as a fighter to catch the leader of a gang dealing drugs on the streets

When the NCIS team receives a cryptic, urgent message, Fatima and Rountree must work together to solve the case. Also, Kilbride plans to visit his son, and Callen asks Sam to be his best man.

The NCIS team is tasked with assisting NCIS’ cold case homicide unit with a case from 2003 and a missing Navy petty officer. Also, Kilbride and his son, Alex, work to rebuild their relationship.

The NCIS team must investigate when a Navy reservist is stabbed and his lab full of pesticides and insects is ransacked. Kilbride offers Sam the interim operations manager position. Rountree thinks about his future.

When four people, including a CIA officer, are shot and killed in broad daylight, the NCIS team suspects the attacks have something to do with DRONA. Also, Pembrook meets with Callen and gives more insight into his past.

When an ATF agent goes missing, the agency seeks help from the NCIS team to investigate stolen military-grade weapons and locate the agent. Also, Callen and Anna continue to plan their wedding, Rountree’s sister interviews for medical school, and Sam encourages his father to take part in the drug trial.

The NCIS team continues the case with ATF and the stolen weapons. Also, Callen and Anna decide on an impromptu wedding.