Patton Oswalt announced the release date Monday

By David Canfield
September 18, 2017 at 03:16 PM EDT

We’ll get to read one final page-turner from Michelle McNamara, a true crime writer and the late wife of comedian Patton Oswalt.

Harpercollins announced on Monday afternoon the publication of I’ll Be Gone in the Dark: One Woman’s Obsessive Search for the Golden State Killer, McNamara’s true crime thriller centered on the unidentified serial killer and rapist — dubbed in the book “The Golden State Killer” — who murdered at least 10 people and raped at least 50 in Southern California between 1979-1986. The book will go on sale Feb. 27, 2018.

In April of last year, McNamara died unexpectedly at age 46 of a lethal combination of drugs in her system and a then-unknown health condition. A celebrated true crime writer and the founder of her website True Crime Diary, she was known for reporting out fascinating but under-the-radar cases in an engrossing narrative style. She was survived by her seven-year-old daughter, Alice, and husband Oswalt, who recently became engaged to actress Meredith Salenger.

I’ll Be Gone in the Dark was unfinished at the time of McNamara’s death, despite her many interviews with victims, analysis of police reports, and time spent in online communities similarly interested in discovering the killer’s background and identity. According to Harper, the book was ultimately compiled by McNamara’s lead researcher as well as a close colleague, and — as was typical with the author’s work — will interweave the juicy crime narrative with a portrait of McNamara’s obsession with uncovering the history and finding the truth.

I’ll Be Gone in the Dark will include an introduction written by Gillian Flynn and an afterword by Oswalt.