This episode contains descriptions of violence and sexual assault. Use your best judgment.

Regina Reynolds was a student at Morrisville State College in 1975. Her friends and family called her Reggie. She was well-liked.

On November 6th, she needed to get to campus. So she started walking, hoping to hitch a ride.

Around 5 p.m., someone stopped and asked if she needed a lift. Regina got into the car.

She didn't make it to campus though, ever again. Regina was murdered.

From A&E, this is Cold Case Files.

Regina was missing for four days before her roommates called the police. Her friends told the investigator that they were suspicious when Regina missed the dinner date they had planned.

Investigator Jean Rivenberg was assigned to the case.

It was unusual to have a dinner date and that show up, especially with a boyfriend and a violin. The other people involved didn't make sense that she would just take off. She didn't have the reason to take off.

The investigators began to think the worst had happened after a week with no leads. They interviewed Regina's boyfriend, Robert McDonald, one of the last people to see her alive.

I think that's one of the things that made it so hard is because other people are looking at you too, like you might have done something.

It's difficult to go through that. You're very desperate for hope that she's going to be okay. The longer day after day went on, it was very difficult.

On November 19th, two weeks after Regina had gone missing, her body was found 50 miles away at Otiska Lake.

A fisherman was heading to the water when he found a naked body in the weeds. This is Detective Dave Paul.

You could tell at that particular time you're looking for a very serious killer. Just by the way, he threw the body away. And he did throw it away just like you would have rolled kill.

The acid over made no attempt to cover or up or anything.

Regina had been killed by a single stab wound to the heart with a large double-bladed knife. Seaman was found inside her body and preserved on a slide for future testing.

At that time we didn't have DNA but we did send it down to the lab to see if we could get the coating whether it was blood A, B, whatever. And we couldn't get that done at the time.

But all that was done was an act of down to a couple of million people if we got the blood typing.

Detective Ray Salvi was part of the team of investigators focusing on the crime scene. While at the scene, he walked to the top of the nearest hill, likely the spot where the killer was when he threw the body.

While standing there, something caught his eye. This is Detective Salvi.

When I looked down at the scene there, I saw this plastic container which was similar to what a businessman would carry business cards in.

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