It's a classic case of how precious life is.

Here's a guy that's going to call this wife.

He's been separated from his military assignment from her.

He's probably looking so forward to making that call,

and she's looking forward to receiving that,

to then how tragic that situation becomes.

I'm Scott Weinberger, investigative journalist and former deputy sheriff.

I'm Anisega Nicolasi, former New York City homicide prosecutor

and host of investigation discoveries to conviction.

And this is anatomy of murder.

Today's story takes us to the Caribbean to the island of St. Thomas

to tell you the story of a cold case that was ultimately solved

with the help of a surprising star witness, the victim himself.

The brutal 1993 murder of Navy Lieutenant Dana Bartlett,

along with the assault on two fellow sailors,

went unsolved by local police for nearly 18 months

before the veteran agents of the NCIS,

also known as Naval Criminal Investigative Service,

stepped in and joined the hunt for his killer.

And not only did this team ultimately deliver justice for the victims,

but it would help write the playbook for newly formed cold case squads nationwide.

31-year-old Lieutenant Dana Bartlett was a Navy helicopter pilot

...