I’ll Be Gone In The Dark, the 2018 true-crime bestseller from the late Michelle McNamara, contained years of research that unquestionably helped law enforcement arrest the Golden State Killer. McNamara even helped coin that nickname for the predator formerly known as the East Area Rapist, who committed 50 rapes and 12 murders while terrorizing California in the 1970s and 80s. Sadly, McNamara passed away two years before the publication of her book and the arrest of Joseph James DeAngelo, who’s expected to plead guilty on June 29. The book not only illuminates her dogged pursuit of the truth, but also the public awareness that she generated, both of which led to renewed law enforcement attention for a 30-year-old cold case.

Following McNamara’s death (due to an accidental overdose of prescription drugs coupled with a medical condition), her husband, Patton Oswalt, resolved to make sure her book was published. He greenlit the manuscript’s completion, and he’s now appearing onscreen in HBO’s six-part docuseries (directed by Liz Garbus), which includes interviews with survivors, investigators, and those who knew Michelle well. Her empathy, and her non-sensationalized treatment of the material, made the book one hell of a read, and that comes through on the series. Patton read aloud from Michelle’s book while visiting Seth Meyers on the day of DeAngelo’s arrest, and he was gracious enough to speak with us ahead of the series’ debut (this talk took place just prior to this past weekend’s Fyre Fest-esque Trump rally in Tulsa).

It’s now customary for us to greet each other by asking if the other’s alright during the pandemic.

Well, are you keeping safe?

For now, but I’m in Tulsa, and there’s an event this weekend.

Oh god!

People aren’t thrilled about a rally happening.

Trump is so confusing. He canceled it, but it’s back on?

They nixed the Juneteenth date. It’s now happening on Saturday.

Oh, Christ, I’m so sorry. I hope you stay safe! Look out for that goddamn Boogaloo group, which is some kind of white supremacist thing. They’re trying to start a race war, so they dress like Antifa, but they shoot cops? It’s, like, fucking terrifying.

This is when we need your Constable Bob from Justified to save the day.

Oh, thank you!

Before we talk about the HBO series, I can’t resist mentioning one of my favorite passages from Michelle’s book — an anecdote about how you gave her a pep talk about Rocky Balboa to help her stay on her writing path.

[Laughs] I was just trying to find some imagery or a narrative that she could use, and that was Rocky. Like, if you watch the original film, he’s insanely out of shape and just has to rebuild from nothing. That was the metaphor I used, and I hope it doesn’t come off as clumsy, but it was the best that I could come up with. Yes, that was the pep talk I gave her on the book, godddd.

Michelle’s writing felt so human, and that only added to that vibe. She also suggested that you silently mouthed jokes to rehearse while washing dishes.

Oh yeah, I washed dishes because that really fed into my OCD and my, like, assembling of things in my head.

Obviously, the series has plenty of somber and emotional moments, but is also a celebration of Michelle’s work. When did you find out it was happening?

I remember that Liz approached me to pitch the idea, and I really, really liked her as a filmmaker. I knew that she would be great at figuring out the narrative correctly. And when I found out, we were in discussions with Liz, and that’s just kind of how it came together. We were working on the series when [Joseph James DeAngelo] got arrested.

You learned about the arrest when the cameras were rolling.

Yeah, we had been working on the documentary, and then then it happened, so they caught it on camera. Crazy, yeah, it was nuts.

You also pop into the series in several places.

Well, I don’t know that I participated that heavily, but I did make sure and turn all the materials over to Liz and her team, and then I wanted the focus to be on Michelle and the survivors and the investigators. That’s what I wanted it to be.

Very clearly, you were supportive of her work.

I mean, I tried to be as supportive as I could.

It isn’t easy to be married to a writer, I imagine?

[Laughs] Well, since we were both writers, we both understood where we were each coming from at the time.

In your afterword, you wrote that you guys initially bonded over your mutual serial-killer knowledge.

Yeah, definitely. That’s in there. I wanted to definitely do the afterword because I wanted Gillian [Flynn] to do the intro to bring us into her world. She’s such an amazing writer that I wanted her to do the intro, and I would do the very last part. I also wanted the last voice in the actual voice to be Michelle’s, and that’s the “Letter To An Old Man.”

That “old man,” Joseph James DeAngelo, is expected to plead guilty.

I believe so! I think it’s the day after the first episode airs. I’ll be watching, and I think what’s more important that the survivors and the victims’ families will be watching, and the same with the investigators.

In addition to law enforcement, Michelle’s fellow citizen investigators, Paul Haynes and Billy Jensen, were incredible.

Yes, they assembled the book. I handed everything over to them and was like, “Please, just help me get this done.” I didn’t want this work to remain unfinished. I don’t think I would be able to live if that was the case.

HBO

When it came to Michelle’s writing, when did you realize how skilled she was?

I mean, right away. Just when you talk to her, you can see what an original mind she had, and how engaged with everything she was, and so reading her writing, to me, it wasn’t surprising how amazing she was.

Are you surprised that her book, and her push for DNA, led to an arrest, and did you gave any gut feeling about it?

Actually, I did not know how this thing would turn out. Again, it was another very happy and pleasant surprise, that the victims’ families and survivors would feel some justice, I hope.

You talked a lot in your Annihilation special about your grieving process, and this opens another door of that, no doubt.

It’s just an ongoing process. I found love again, which I didn’t think would happen. It’s still gonna be day by day for a long time.

So, this docuseries will air over six weeks, and I think it nails the obsessive feel of the book because I binged it in one day.

Wow. It’s a tough one to watch, too.

But like I said, there are positive moments, and Michelle’s vibrant personality was apparent. I did chuckle while reading the book when Michelle formally ruled out Tom Hanks as a suspect due to his Bosom Buddies schedule.

Yeah! That, and she really was able to capture how there is a level of obsession with this subject. And thank you so much for taking the time to watch it all, I really appreciate it. And stay safe. Please! This weekend, if you’re going to go protest in Tulsa or have friends who are going out there, tell them to be very careful and aware, okay? I’m serious, please be safe.

HBO’s ‘I’ll Be Gone In The Dark’ premieres on Sunday, June 28 at 10:00pm EST.