HBO has released a new trailer for its upcoming true-crime documentary series I'll Be Gone in the Dark. The series is based on the book of the same name by Michelle McNamara, who passed away in 2016. McNamara had been investigating the criminal, known as the Golden State Killer, prior to her untimely passing. This series will bring her investigation to life.

The trailer opens up with several accounts from people who encountered the killer. We then see how Michelle McNamara began investigating these crimes, which had taken place over a number of years but weren't all that well known at the time. It also dives into the challenges that existed in trying to complete the book that the series is based on following McNamara's passing. Her husband, comedian Patton Oswalt, appears in the documentary and dives into that process.

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I'll Be Gone In the Dark is a six-part HBO documentary series. It centers on Michelle McNamara's investigation into the dark world of a violent predator she dubbed the Golden State Killer. Billed as "a timely inquiry into our macabre preoccupation with true crime and a cautionary tale of the dangerous lure of addiction," the series is a meditation on obsession and loss. It chronicles the unrelenting path of a mysterious killer and the determination of one woman to bring the case to light.

Michelle McNamara passed away of an accidental overdose. With the help of Patton Oswalt, McNamara's work was handed to a group of trusted individuals who completed the book, which was released in February 2018. Two months later, the elusive killer was captured. The series is directed by Liz Garbus, Elizabeth Wolff, Myles Kane and Josh Koury. Wolff recently spoke during a virtual panel at the ATX Television Festival and had this to say about it.

"Writing is solitary and documentaries are such a collaboration. We got to go to work every day and work with 20-plus people. These were dark stories, and it is incredible how much you can accomplish when you're interacting with people and doing it together. And I think that there was a great tragedy in getting to know Michelle's story for me, because I kept on thinking, 'Oh my god, I wish she had what I had on this project when she was writing that book. Would it have helped her and would it have turned out differently?'"

The Golden State Killer terrorized California in the 1970s and 80s and was responsible for 50 home-invasion rapes and 12 murders. The investigation challenged police for decades. The documentary makes use of original recordings and excerpts from her book read by actor Amy Ryan (The Office, Central Intelligence) to tell the story in Michelle McNamara's own words. I'll Be Gone in the Dark debuts on June 28 on all HBO outlets. Be sure to check out the new trailer for yourself.

I'll Be Gone in the Dark Poster