HBO is turning late crime author Michelle McNamara's book on the Golden State Killer into a docu-series.

According to Deadline, the network is already in production on an adaption of I'll Be Gone in the Dark: One Woman's Obsessive Search for the Golden State Killer just a month after purchasing the rights and mere days after former police officer Joseph James DeAngelo was arrested on eight counts of first-degree murder based on DNA evidence. News of his capture went viral on social media with many crediting McNamara's book for the big break in the case.

I'll Be Gone in the Dark chronicled McNamara's obsessive journey to find the man responsible for committing over 50 sexual assaults, at least 12 murders and over 100 burglaries in California during the '70s and '80s. The case had gone unsolved for more than 30 years until DNA evidence connected DeAngelo to the crimes, leading to his arrest by the Sacramento Sheriff's Office on April 24.

McNamara, who dubbed the serial killer behind these crimes as the Golden State Killer in her book, died suddenly in her sleep in 2016 before she could finish it. The book was completed by those closest to her including longtime researcher Paul Haynes, colleague Billy Jensen, writer Gillian Flynn, who penned the introduction, and her husband Patton Oswalt, who wrote the afterword.

Oswalt will also serve as executive producer on the docu-series and What Happened, Miss Simone's Liz Garbus has signed on to direct.

Michelle McNamara and Patton OswaltMichelle McNamara and Patton Oswalt