A reign of terror casts an ominous cloud over the City of Angels. A demon is murdering innocent young women. Suddenly the slaughtering stops. The elusive killer is dubbed the "Grim Sleeper."

But he wakes with a vengeance. Police are stumped, until the killer makes one critical mistake. He lets one of his victims live.

"He thought I was dead," said Enietra Washington.

The 1980s were an ugly era in South Los Angeles. Crack wars were rampant and crime was at an all-time high. Jill Stewart, former LA Weekly managing editor , says it was the perfect time for a serial killer to strike.

"I think it allowed serial killers to operate in silence -- you couldn't tell who was killing who, it was just called random violence," said Stewart.

So when Debra Jackson was found shot to death and dumped in an alley, police first assumed it was a random drug hit. Until the bodies of more and more young women started to pile up.

Henrietta Wright, 35, and Barbara Ware, 23, are found shot dead, their partially clothed bodies left in dark alleys. Police received an anonymous 911 call from someone saying he witnessed a man dumping Ware's body Police actually suspect the caller may be Ware's real killer, but have no proof.

Three dead women all shot and dumped in nearby alleys. LAPD Homicide Detective Daryn Dupree says it may have been the first sign a serial killer was on the prowl in South L.A. And then Bernita Sparks turns up dead. Cops are stumped when Mary Lowe turns up dead in another alley.

This time, cops catch a much needed break: A witness tells police he saw Lowe getting into a souped-up orange Ford Pinto with an unknown man.

"So forever the police had been looking for old orange pintos they even did DMV studies of every orange Pinto in the entire California area," said Stewart.

But before they can locate the car, they find another half-naked body in an alley: 22-year-old Lachrica Jefferson.

"He never really went outside that comfort zone," said LAPD Homicide Detective Daryn Dupree. "He knew the alley ways, knew the people, he knew everything."

The killer had a definite M.O. But detectives also notice a pattern with his victims: Most of them had cocaine in their bodies. Police suspected the killer was luring the women into his car with the promise of drugs, but instead, giving them a bullet.

Despite the similarities in many of the murders, cops still won't confirm or deny if they did indeed have a serial killer on their hands. The LAPD starts to piece together a blueprint linking seven of the murders. All are shot by a small .25-caliber handgun.

"All of these murder victims were all shot from left to right front to back in a downward direction so that was consistent with being seated in the right front passenger seat of a vehicle and the driver turning towards you and shooting you," said Beth Silverman, deputy district attorney, Major Crimes Division.

But the key would be the DNA. It was all swabbed off the victims' breasts. And it all matched.

"Lo and behold we wound up with the same DNA profile," said Silverman.

But at the time DNA was not an advanced crime-fighting tool. There was no database, and no way to identify the killer.

"He was still a needle in a haystack," said Det. Dupree.

But instead of warning the public and the women of South L.A., Jill Stewart says, the LAPD made a highly controversial decision to keep the serial killer theory a secret.

"They were trying to figure out who he was. They didn't want to spook him, send him out of state, for example, but that's a double-edged sword," said Stewart. "He just thinks he's free to just go ahead and keep doing what this evil son of a bitch has been doing all this time."

And that's exactly what he did. The serial monster, was soon back in business and on the prowl for his eighth victim.

But when he found Enietra Washington, his number was up.

Few people can say they've survived the wrath of a serial killer. Enietra Washington is one of them.

"I'm the only survivor we know of," said Washington.

When Washington, a home healthcare provider, accepted a ride from a friendly man driving an orange Pinto, she had no idea she was getting into the car with the notorious "Grim Sleeper."

"I was going to a party," said Washington. "He said, 'Well, can I go?'"

In the car, the madman shot Washington point-blank in the chest, and then began to savagely rape her.

"I said 'How can you kiss and do all this while I'm bleeding?'" said Washington.

After hours of torture, Washington made a life-or-death decision: She grabbed for the door handle and jumped.

"I believe that he thought that I was going to just lay there and I would die in the street," said Washington.

But she's a fighter. Doctors retrieved a small .25-caliber bullet from her chest. Ballistics revealed it was a match for the same gun used on the Grim Sleeper's seven other victims.

Cops finally had someone who could put a face on the killer. Washington helped a police artist with a composite sketch. She also told detectives about a bright light inside the car, possibly the flash from a camera.

"All I remember is that flash being in front of my face and fighting him," said Washington.

The LAPD still kept the serial killer theory a secret.

"This was a live acting killer that the girls in South L.A. didn't know about," said Jill Stewart, former managing editor of the LA Weekly.

Then the killings stopped, and the killer went eerily quiet. The LA Weekly dubs him the "Grim Sleeper."

And cops are on pins and needles. They know this isn't over.

"He was the longest running serial killer in the United States west of the Mississippi," said Stewart. "He had been operating longer than anyone else that was known, and he stopped for 13 years. Or it looked like he did."

Then suddenly he wakes. His thirst for blood rekindled with Princess Berthomieux, a 15-year-old runaway, and Valerie McCorvey. Both are found strangled to death -- not shot.

But it wasn't long until he went back to his primal instinct. Jenecia Peters, a mother of 4-year-old, is found shot with a small-caliber handgun. The killer stuffed her body in a garbage bag.

"The DNA that linked the defendant in this case in her murder came from the zip-tie that sealed that bag," said Silverman.

By now DNA was a common crime-solving tool. But LAPD Detective Daryn Dupree says the Grim Sleeper's DNA wasn't in any of their databases. But there was a possible solution: a groundbreaking DNA test that could link the killer's DNA to any family member found in the database.

"One person in prison lit up like a Christmas tree," said Jill Stewart. "Turned out to be the Grim Sleeper's son."

Chris Franklin had just gotten out of jail and was living in a house in South L.A. with his mother and father, Lonnie Franklin Jr., a retired garbage man for the city.

Police knew they had their man, but they had to prove it. So they came up with this elaborate undercover sting that required them to pose as workers at a pizzeria.

Surveillance video obtained by Crime Watch Daily shows Lonnie Franklin Jr. inside a local pizza restaurant.

"One of the undercover officers acted as his busboy at this pizza party and was able to collect multiple samples from Lonnie Franklin," said Silverman. "But they were able to develop beautiful, complete DNA profiles from the piece of pizza."

The LAPD then assembled a special Grim Sleeper task force to arrest Lonnie Franklin Jr. at home for the murders of 10 women and the attempted murder of Enietra Washington. What they found was a house of horrors. Police uncover one of the most gruesome trophy rooms of any killer ever caught: A treasure trove of guns, morbid mementos, photos of women, some presumably dead, and pornographic home videos of Lonnie Franklin Jr. with more than 160 women.

"Mr. Franklin would take a professional pornographic video and he would splice in there something he's doing with a female, sexually, and then you go back to the actual pornographic video," said Det. Daryn Dupree.

But the key piece of evidence was a Polaroid picture found buried between two pieces of plywood. It was a picture of Enietra Washington.

In video of the interrogation of Lonnie Franklin Jr., detectives confront him with that picture, and a photo of every single woman he's accused of killing.

During the interrogation, Franklin tells police these women are too ugly for his taste.

WATCH: 'Grim Sleeper' Lonnie Franklin LAPD interrogation

After decades of terror the families of the victims finally get their day in a Los Angeles courtroom. Lonnie Franklin Jr., the Grim Sleeper, was convicted of murdering nine women and one teenager, and the attempted murder of Enietra Washington. But the Deputy District Attorney wonders how many more of the Grim Sleeper's victims are out there.

Franklin was sentenced to the death penalty exactly 31 years to the day of his first victim Debra Jackson in 1985.