WHEN A NAVY OFFICER VANISHED OFF A SUPPLY SHIP ALONG WITH $8,600 DURING THE VIETNAM WAR, HE WAS LABELED A DESERTER AND A THIEF, BUT WAS THERE SOMETHING MORE TO HIS DISAPPEARANCE?

"48 HOURS: NCIS: A SAILOR'S HONOR"

Tuesday, May 29, 10:00 PM, ET/PT

When a young Navy officer vanished without a trace along with $8,600 from a supply ship during the Vietnam War, he was classified as a deserter and a thief. But his family believed something sinister happened. Can NCIS agents solve a decades-old cold case?

NCIS agents reveal the hunt for answers in the disappearance of payroll officer Andy Muns, the organization's oldest cold case, in 48 HOURS: NCIS: "A Sailor's Honor," to be broadcast Tuesday, May 29 (10:00 PM, ET/PT) on the CBS Television Network.

48 HOURS: NCIS is a six-part series from the award-winning team behind 48 HOURS that takes viewers inside the difficult cases faced by NCIS agents, who investigate murders, track killers and use the latest technology to solve cases that once seemed unsolvable. Rocky Carroll, star of CBS' drama series NCIS, narrates each edition.

In 1968, Muns was a 24-year-old payroll officer aboard the U.S.S Cacapon, stationed in the Philippines, when he mysteriously disappeared. He was never seen nor heard from again. The Navy investigated, but he was classified as a deserter and a thief.

"He would have never taken that money. It just didn't make sense. We knew that something bad had happened," says Mary Lou Taylor, Muns' sister. "Somebody killed my brother."

Three decades after her brother went missing, Taylor tracked down the original Naval investigator who admitted he had been haunted his whole life by this case. He told her he believed something terrible had happened to her brother, but he couldn't prove it. The investigator would become part of her efforts to convince the NCIS to reopen the case.

In 1998, Taylor got a call from Pete Hughes, then head of the NCIS cold case squad.

"She had explained to me certain things she had done on her own and just hearing that just screamed she needed assistance," Hughes says.

"There's no evidence. There's no crime scene. There's no witnesses," says retired NCIS Special Agent Jim Grebas. "This case was unsolvable. But one thing about Pete and I, we had a good track record for solving the unsolvable."

The agents began by tracking down crewmembers of the U.S.S. Capacon, specifically focusing on anyone who might have made odd statements about Muns after his disappearance.

That led them to Michael LeBrun, who originally told investigators that Muns may have gone scuba diving and drowned, which raised a red flag for the agents. Trouble is, Muns was last seen at midnight, meaning if LeBrun's theory was correct, Muns went diving alone in the dark. "That's not gonna happen," says Hughes.

"I cannot tell you what happened," LeBrun told the agents during an interrogation, to be broadcast on 48 HOURS: NCIS. "If I tell you what happened, I'm gonna be making something up."

But suddenly, LeBrun surprised the agents with a new theory. One where he might have played a role in Muns' disappearance.

Was it the clue the agents needed to bring charges and restore honor to the fallen sailor?

48 HOURS: NCIS: "A Sailor's Honor" is produced by Jonathan Leach. Marlon Disla and Phil Tangel are the producer-editors. Jack Pyle is the editor. Rob Klug is the director. Anthony Batson is the executive producer. Susan Zirinsky is the senior executive producer.

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