Review: HBO's 'I'll Be Gone in the Dark' shines as tale of two obsessions

The crimes of the Golden State Killer are horrific: Over 50 rapes and at least 13 murders committed in California in the '70s and '80s.

But his is only one of the obsessions examined in HBO’s six-part documentary “I’ll Be Gone in the Dark.” The other is the compulsion of crime blogger and amateur detective Michelle McNamara to find a murderer that authorities had pretty much stopped looking for.

McNamara was the wife of comic and actor Patton Oswalt. They had a young child, Alice. And yet she spent countless hours piecing together evidence, spinning theories and running down rabbit holes late at night, trying to catch a killer who’d had no direct effect on her life.

It likely killed her. McNamara died of a drug overdose — she’d secretly been taking a mix of things to help fuel the search — before she could finish a book on the killer. The book was finished by others and became a huge hit. And eventually, as the book was atop best seller charts, McNamara’s prodding led to the killer’s arrest.  

All of this has been laid out in headlines and in the book itself. But filmmaker Liz Garbus has painted a far more complete and compelling picture with the documentary, which offers context aplenty even as it can’t quite explain what drove either the killer or writer. Both mysteries endure.

But Garbus has plenty of footage of McNamara being interviewed, she has tapes of her investigations, home movies and Oswalt reminiscing and clarifying. She’s aided mightily by Amy Ryan’s narration, which melds smoothly with McNamara’s own voice. Re-enactments take us through the killer’s moves and many victims come forward to speak, becoming more than just victims.

A parade of rape enactments threatens to drag and a halo hangs dangerously over McNamara’s head at times. But “I’ll Be Gone in the Dark” always rights itself and ends up both engrossing and enlightening. It doesn’t have all the answers — no one does — but it asks the right questions in the right way.

“I’ll Be Gone in the Dark”

GRADE: B+

10 p.m. Sunday

HBO

Tom Long is a longtime contributor to The Detroit News.