For 20 years, the Green River Killer terrorized the Northwest, leaving a trail of women's bodies and very few clues.
He was on the loose until late 2001. But late last year, Gary Ridgway pled guilty to killing 48 women. The plea was part of a controversial deal -- the killer's life in exchange for the truth.
But to get that truth, detectives had to go on one of the darkest journeys imaginable -- inside the mind of a serial killer. They spent six months living with Ridgway, taping every conversation.
60 Minutes showed the tape, which was released earlier this year, and Correspondent Dan Rather talked to the detectives who have spent the past two decades chasing America's worst serial killer.
Hundreds of hours of taped confessions released last February offer an unblinking look at a killer both monstrous and mundane. It shows the dark side of Ridgway, the side that only his victims had seen until now.
"I was working second shift and go pick up a woman on the way home," says Ridgway on tape. "That way, I had the mornings free to go back and bury her."
Ridgway had the same job as a truck painter for 30 years. He remembered his victims by the shift he worked that day. He was a man who viewed his killing spree as his greatest accomplishment.
A handful of detectives listened to a recounting of the details of Ridgway's grisly crimes for more than six months. And for most of them, it was familiar ground.
In 1982, when the bodies of three women were found in or near Washington state's Green River, homicide detective Dave Reichert was called in. Today, he's the county sheriff.
"I knew I was gonna be talking to pure evil, a monstrous killer. But I had a job to do, and every one of those detectives that walked into that room probably wanted to throttle him," says Reichert. "But they all had a job to do and they did it."
Det. Tom Jensen joined the hunt for the Green River Killer in 1984 – and has been on the case ever since.
"Gary Ridgway was probably not the most intelligent person you'll ever meet. He's certainly undereducated, but he does have a talent for killing," says Jensen. "He became what I called a serial killer savant. He was not good at anything else, but he could stalk and kill with the best of them."
Ridgway was behind the country's longest-running serial murder spree. In and around Seattle 20 years ago, the bodies of dozens of women, many of them prostitutes, were found dumped in the deep woods, in parking lots, on a playground.
At one point, more than 50 detectives were working to solve the crimes. For many of them, catching the killer has been more than a case. It's been a career.
"Each crime scene that you go to, you know you're walking in his footsteps, and you are trying to put yourself in his shoes," says Reichert. "What did he do? Where did he walk? What was he thinking? All of these thoughts are going through your mind when you're processing that scene, trying to find evidence."
By the late '80s, the killings seemed to have stopped. Public interest lagged, and money to the investigation was cut. The entire Green River evidence collection was boxed and bagged, stacked and stored.
Only one man, Det. Jensen, continued on the case. He worked alone for nine years, carrying all the responsibility for solving nearly 50 murders. But the case still torments him.
"It reached a point where I didn't really know where it would go if I was gone," says Jensen.
But Jensen was patient, waiting for DNA testing to improve enough to use on some of the old evidence found on victims in the Green River case. He wanted to compare it to a DNA sample that detectives had taken from one of their top suspects years before.
That suspect was Ridgway, a Seattle area native with no known juvenile record. He had been married three times and had one son. He drew police attention when he was accused of assaulting a prostitute.
Ridgway, however, had passed a polygraph test, and a search of his home had turned up nothing.
So why didn't he leave town? "He thought he was going to get away with it," says Jensen. "I believe he thought he was sitting pretty."
By 2001, 14 years after police first suspected Ridgway, DNA testing had vastly improved. And this time, there was a match.
"I said, 'Tom, what are you trying to tell me? That we've got a suspect,'" recalls Reichert. "And he smiled, and said, 'Yes, sheriff. And he reaches in his coat pocket and he pulls out an envelope. And he says and I've got him right in here.'"
"He didn't even have to open it," adds Jensen. "He immediately just picked it up and said 'It's Gary Ridgway, isn't it?'"
Police and prosecutors were eventually able to physically link Ridgway to seven cases. But dozens more women were believed to be among his victims.
So, to get answers on the other cases, police and prosecutors struck a deal with Ridgway. If he told the truth about all the killings, he could avoid the death penalty.
"From the very beginning, it was all about 'I wanna save my life and I'll tell you what you need to know,'" says Reichert. "And they talked about having information on 60 or more dead bodies."
Once the deal was signed, detectives gathered to begin questioning the man they'd chased for 20 years.
Among them was Det. Randy Mullinax, who had been with the case at the very beginning.
Did Ridgway remember much about his victims? "No, and that was one of the things, that when we went into the interview, we had all of the victims' photographs together and our information ready," says Mullinax.
"We learned within hours that he was not going to remember the faces. The faces of these little girls and these young women didn't mean anything to him."
"To me, women are something to have sex with -- kill and take the money back," says Ridgway on tape.
Faced with questioning a killer who couldn't remember his victims, detectives decided to do something unique to get at the truth. They secretly moved Ridgway out of jail and into their headquarters, where he lived in a small office in the center of the room for nearly six months --sleeping on a bare mattress.
He spent each day under heavy guard -- surrounded by the men and women who had once tried to catch him.
"It was the strangest experience of 25 years in law enforcement," says Mullinax. "To have him say good morning or goodnight to you for six-plus months was very strange. It was very strange for all of us."
Every day, Ridgway would come to a room, take a seat before the camera, and begin to answer questions.
Behind him, his defense attorneys across from him, were the detectives who had waited decades for this chance.
Sometimes, the truth had to be pulled out. But eventually, Ridgway admitted stabbing a small boy as a teenager, and acknowledged having problems with women -- beginning with his mother.
"I hate women," he said on tape.
In six months, police may have spent more time with a confessed serial killer than any other investigator in the country.
"Here's the success of Gary Ridgway. He's a very cunning individual. He picked the right victims," says Reichert.
"He picked young girls who were working on the street as prostitutes. She gets into the car and disappears. There's no struggle. There's no screaming. They drive off into the night and she's gone. And she doesn't come back."
To jog Ridgway's memory, detectives took him to the sites where he had dumped the bodies.
Crammed into a van and shot by a night scope, it all looks like some kind of odd hunting expedition. And it was. Ridgway led detectives to four more bodies, and Det. Jon Mattsen was along for every ride.
"He would come alive when we would actually go out on these trips. And we never really told him when we were gonna be going out in the field," recalls Mattsen. "What we would do is we would just show up -- sometimes at 3:30 or 4 in the morning."
Again and again, when Ridgway was not forthcoming, detectives brought down the hammer. And all the answers poured out, all except the most important one. Why?
"That's the million dollar question, right," asks Reichert. "A lot of people asking why in the hell did he do it?"
"Because they were prostitutes and I killed them because I wanted to kill them," said Ridgway on tape.
"It took us five and-a-half months to pull the truth out of him, weeding through a lot of lies," adds Reichert.
"He is a person, this is very clear, who in my opinion has no remorse. That when he looked into my eyes, and the eyes of the other detectives, and he said 'I killed because I wanted to,' I believe that."
Copyright 2004 CBS. All rights reserved.