Thirty years after a serial killer's reign of terror, his final victim is speaking out.

>> Read more trending news

"The pain was horrible," said Mary Ann Marker, who was shot in the face by Gary Allan Robbins.

Robbins lived in Pittsburgh, and targeted women in Pennsylvania and other states. When he attacked Marker, he first knocked on the door of her Somerset County home and asked for directions to the Maple Festival. When the bullet hit her, she fell to her knees but managed to lock the front door of her home.

"I know God had to be with me that day. He had his hand on me or I would not be here. There's just absolutely no other explanation," said Marker.

“God only knows how many women fell victim to this guy,” Jefferson County, Ohio, Sheriff Fred Abdalla said.

Abdalla linked Robbins, a door-to-door insurance salesman who lived in Squirrel Hill and Murrysville, to the abduction and murder of Christine Campbell in 1987. Robbins also was connected to the abduction and sexual assault of a woman from Butler County, and Abdalla said Robbins was suspected of murdering women in Michigan and Maryland as well.

Abdalla said Robbins normally bound and gagged his victims with a scarf, and then shot them.

“If (Marker) didn't survive, God only knows how long it would have took us to find that guy. But she had to be a tough lady, she had to close that door on this guy,” Abdalla said.

After shooting Marker in the face, Robbins took off in his car. That's when Marker, despite the fact that she had been shot and was bleeding, made it to the phone and called a Pennsylvania State Police barracks, where her husband worked as a trooper. He was out of town that day, but other troopers and police swarmed to the home.

Robbins made it to Route 219, about eight miles from her house, before a state trooper spotted him and pulled him over. At that point, Robbins turned the same gun he used to shoot Marker on himself.

Marker received commendations from the state police and even former President Ronald Reagan. For years, she struggled with PTSD, and said counseling helped. Despite the fact that her survival and phone call led police to stop a killer, Marker said she doesn't see herself as a hero.

"People say, yes, I'm a hero, and I'm very honored. I'm very humble, but no, I don't consider myself a hero," said Marker.