WHEN THE INVESTIGATION OF A MURDERED NAVY PETTY OFFICER GOES COLD FOR NEARLY TWO DECADES, A NCIS AGENT GOES UNDERCOVER TO TURN UP THE HEAT ON A SUSPECT

"48 Hours: NCIS: The Sting"

Tuesday, June 13, 10:00 PM, ET/PT

NCIS agents take viewers inside a risky undercover operation to turn up the heat on the key suspect in the murder of a Navy petty officer, in 48 HOURS: NCIS: "The Sting," to be broadcast Tuesday, June 13 (10:00 PM, ET/PT) on the CBS Television Network.

Mervin "Sonny" Grotton left work at the Naval Education Training Center in Newport, R.I., for his home in Belfast, Maine. As he walked to the front door that day in 1983, he was shot dead.

"There was someone hiding by the woodpile that was piled in the driveway, and for some reason they shot my dad," says Grotton's daughter, Rosalyn Grotton.

"He had the biggest heart and was so giving and so honest and so hard working and so loving," Grotton says of her dad.

Local police initially suspected his wife, Norma Small, but they didn't have enough evidence to arrest her. Then the case went cold for nearly two decades until a team of NCIS agents took another look.

"I grew up in a military family," says retired NCIS agent Dave Truesdale, a tough, tattooed law enforcement professional with a black belt in martial arts. "Any time that I see a military member hurt by somebody, it does push me to resolve that incident."

In this case, the agents had a hunch that Small was involved in some way. As they peeled back the layers, agents say they found out Small had a much different life when her husband was away on duty, one that involved other men. But was that enough to want her current husband dead?

To get evidence, they had to risk their lives by going undercover. Small was their initial target.

"Undercover operations can be very dangerous," says Truesdale. "You have to develop a role or persona, and once you develop that persona, you perfect it. In this undercover operation, I identified myself as Tony."

"Tony" set up a meeting with Small.

Truesdale, who says he likes going undercover because it forces him to think on his feet, also understands the risks. "Best-case scenario, you blow your line," Truesdale says, "worst-case scenario - you get killed."

The investigation would lead police to two men: Boyd Smith, the former boyfriend of Small's daughter, and Joel Fuller. Smith and Fuller denied they were involved. In 2002, Small, Smith and Fuller went on trial for the murder of Grotton. Smith and Fuller were acquitted.

Rosalyn Grotto wants justice for her father's killer. "I believe in an eye for an eye," she says. "I'm sorry, but when you do something like that, the same thing should be done to you."

Narrated by NCIS series star Rocky Carroll, 48 HOURS: NCIS is a six-part documentary series from the award-winning team at 48 HOURS that gives viewers unprecedented access to some of the biggest cases handled by the real Naval Criminal Investigative Service. The series explores the kinds of difficult cases that have inspired CBS Entertainment's successful primetime series NCIS, the #1 drama on television, NCIS: LOS ANGELES and NCIS: NEW ORLEANS.

48 HOURS: NCIS: "The Sting" is produced by Alec Sirken. Paul LaRosa is the senior coordinating producer. Diana Modica, David Spungen and Marlon Disla are the editors. Josh Gelman is the supervising producer. Anthony Batson is the senior broadcast producer. Susan Zirinsky is the senior executive producer.

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