'I'll Be Gone in the Dark' Finale: Golden State Killer's Nephew Shares an Eerie Memory (VIDEO)

Meredith Jacobs

HBO's chilling six-part true-crime docu-series I'll Be Gone in the Dark airs its finale Sunday night, and the final conclusion features a disturbing childhood tale.

The six-part series, based off of Michelle McNamara's book of the same name, investigates the man who was responsible for 50 home invasion rapes and 12 murders in California throughout the 1970s and 80s, dubbed the "Golden State Killer." As you can see in TV Insider's exclusive sneak peek from HBO above, the murderer's nephew is now looking at a moment from his childhood quite differently now.

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HBO's compelling true-crime docuseries tracks the late writer/blogger Michelle McNarama's obsessive quest to discover the identity of the Golden State Killer.

"One night, I was sleeping, and I had to turn over. And I remember opening my eyes and I saw a man, or some man, in a ski mask and he was staring at me," he recalls. "I always wondered all these years, who was that talking to me through his teeth? Who said, 'don't turn around, go back to sleep?' I never discussed it with anybody."

Watch the clip above to see what he's now realized after his uncle's arrest.

In the finale, the arrest of the Golden State Killer, aka 72-year-old former police offer Joe DeAngelo, plays out in real-time, with facts revealed that "illuminate Michelle's prescience in her book's epilogue, 'Letter to an Old Man,'" HBO's synopsis reads. The episode also includes interviews with DeAngelo's relatives that detail early family trauma and his double life as a father and the Golden State Killer, and a chat with his ex-fiancé about what she saw that caused her to break their engagement.

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I'll Be Gone in the Dark, Documentary Series Finale, Sunday, August 2, 10/9c, HBO; streaming on HBO Max