I feel like the person that killed Jimmy had been trained to kill in a military style, and

that's how Jimmy died.

With a quarter turned to his neck, they snapped it.

It was a short life to be killed at 33.

Everybody was shattered when we found out Jimmy had been killed.

33-year-old Jimmy Grimes was known to his friends and family as a prankster with a great

sense of humor.

But behind the laughter and the jovial exterior was a serious cop.

Jimmy was a dedicated police detective in Cumberland, Rhode Island, a town he grew up in

and loved with all his heart.

Early in the summer of 1996, Jimmy reveals to his sister that he's working on an important

criminal case, something that could earn him a nice promotion.

But weeks later, on August 26, Jimmy turns up dead in an abandoned parking lot 15 miles

away from his hometown.

There's no blood, no bullets, and no wounds on the body.

It appears Jimmy has died of natural causes until a medical examiner makes a shocking discovery.

I'm Steve French and this is Unsolved Mysteries, Murder of an Undercover Cop.

Just 1am in Providence, Rhode Island, as two men take a shortcut through a parking lot

in the downtown area and come across a lone vehicle.

Inside they see a man obviously dead, slumped in the driver's seat with the door slightly

ajar and his leg hanging out.

The men immediately call police who arrive on scene and identify the victim as 33-year-old

...