He photographed his victims, he kept trophies, and for 14 years he completely stopped killing,

earning him one of the most unsettling nicknames in true crime history.

The grim sleeper operated in South Central L.A. for over two decades.

And when police finally caught him, it wasn't through traditional detective work.

It was through a piece of leftover pizza

and some seriously

creative undercover work.

Music Lonnie David Franklin Jr. entered this world on August 30, 1952 in South Central Los Angeles. From the outside, he seemed like any other kid growing up in the neighborhood. But by 1975, when he was 23 years old, Franklin's true

nature revealed itself in the most horrific way possible. While stationed in Stuttgart, Germany

with the Army, Franklin and two other servicemen approached

a 17-year-old girl asking for directions. They offered her a ride home. The moment she got in the car,

they held a knife to her throat and drove her to an isolated field where they gang raped her.

Here's the thing that makes this even more disturbing. During the attack, this young woman kept her wits about her in the most extraordinary way.

She pretended to be interested in Franklin.

And he actually gave her his phone number.

When she reported the crime, police used that number to track him down.

Franklin and his accomplices had also photographed the assault,

foreshadowing the documentation obsession that would define his later crimes. Franklin received a dishonorable discharge for this conviction, but the pattern was already established.

Violence against women, documentation of his crimes, and an ability to present himself as trustworthy right up until the moment he wasn't.

Back in Los Angeles during the mid-1980s, women in South Central started disappearing and

then turning up dead. The LAPD eventually connected the dots and realized they had a serial

killer on their hands, someone systematically targeting black women

...