COMEDIAN PATTON OSWALT OPENS UP ABOUT HIS LATE WIFE'S QUEST TO FIND A CALIFORNIA SERIAL KILLER AND RAPIST, IN "48 HOURS: THE GOLDEN STATE KILLER"

Saturday, April 22 (10:00 PM, ET/PT)

Oswalt Tells Tracy Smith: "She had a mind for details of true crime the way that other people have for baseball or me for films"

Comedian Patton Oswalt opens up in his first television interview about his late wife's quest to find the elusive criminal who terrorized Californians by committing 50 rapes and a dozen murders, in 48 HOURS: "The Golden State Killer," to be broadcast Saturday, April 22 (10:00 PM, ET/PT) on the CBS Television Network.

Michelle McNamara, a true-crime writer, had been on the hunt for the killer and was relentless in her search for answers, until her death on April 21, 2016. Tracy Smith and 48 HOURS investigate the horrific case that inspired McNamara's true-crime reporting through interviews with Oswalt, police and those who are carrying on McNamara's work by finishing the book she was writing about the case.

"She had a mind for the details of true crime the way other people have for baseball or me for films," Oswalt tells correspondent Tracy Smith. "She could recall the details of pretty much every late 20th and 21st century crime. It was just in her head."

McNamara was obsessed with a criminal who had committed 50 rapes and 12 murders across California between 1976 and 1986 before he vanished. The killer and rapist would break into homes in the middle of the night and confront his victims - at the beginning they were single women, but he eventually began attacking sleeping couples. Near the end of his spree, he escalated to murder, ensuring he'd leave no witnesses. In 2013, while working on a story for Los Angeles Magazine, McNamara dubbed the suspect "The Golden State Killer."

"He was the bogeyman," says Sacramento County District Attorney Anne Marie Schubert. "He was the man in the bushes that we didn't know who he was and we didn't know when he was going to strike again."

"She started looking at the devastation that this guy wrought," Oswalt tells Smith. "You're taunting the police, you're taunting the population and you're never caught?"

McNamara traveled extensively to retrace the killer's steps, Oswalt says, because actually seeing the places made her writing more accurate. But, the work also took a toll on her.

"I'd go back into the back office and Michelle would just be there... in tears because some road she had gone down had not panned out, and then - it's, 'I now have to start back again from zero,'" Oswalt tells Smith.

She often did retrace her steps and had promising leads in the hunt for the killer. On April 20, 2016, she was driving herself so hard with the search that Oswalt told her to sleep in the next day. He remembers her snoring the next morning, but when he checked on her early that afternoon, she had died.

"It was April 21st, 'Spring's coming and it's all good,'" Oswalt says. "And then, literally within the space of three hours, just annihilation. Like... this world that you're seeing in front of you is just cinders. It's all... just cinders."

Says Billy Jensen, who is working with Paul Haynes to finish McNamara's book: "She thought she was getting real close to finding him. And then she was gone."

48 HOURS: "The Golden State Killer" is produced by Susan Mallie, Lourdes Aguiar, Gayane Keshishyan Mendez and Lauren Clark. Atticus Brady is producer-editor. Michael Baluzy and Jud Johnston are the editors. Peter Schweitzer is the senior producer. Susan Zirinsky is the senior executive producer.

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