Stephen King will turn 70 in September, yet shows no signs of slowing down. Currently, he has “The Dark Tower” in theaters and “The Mist” on TV. September will see the film adaptation of “It” and a book co-written with his son, Owen King, called “Sleeping Beauties.” There are also two Netflix movies due this year, “Gerald’s Game” and “1922,” but don’t ask him when they’re coming out. “I think one is in September, one is in October,” he says. “Hey, listen, I’m only the writer, I’m the last person to know.”

And starting Wednesday, viewers can check out the 10-part series based on his novel “Mr. Mercedes” on DirecTV’s Audience Network. It stars Brendan Gleeson as retired detective Bill Hodges, who is haunted by an unsolved case in which a man in a Mercedes drove into a crowd, killing eight people. He begins to receive messages from “Mr. Mercedes” taunting him, unaware that the killer is Brady Hartsfield (played by Harry Treadaway, a seemingly mild-mannered individual who is also the neighborhood ice cream man). As with many King characters, even the villain is beautifully drawn and complex. “He is sympathetic in the show, and I liked that because it adds to the audience’s unease,” says King. “He’s a monster but the show and Harry’s performance tries to say: Even monsters are heroes to themselves.”

Published in June 2014, King says he couldn’t have predicted how timely the novel would become. He was stopped at a South Carolina motel when he saw a local news bit about a woman who ran her car into a line of job seekers. “But it never crossed my mind that some of the things that have happened since then with people trying to kill and maim innocent people would happen,” says King. “But you have to remember that those people who do those things think they are doing God’s work. Unless you understand that, you can’t really address their problem in a meaningful way.”

King took a break in his busy schedule to talk about what scares him, what makes a good adaptation, and where his acting career is headed.

I’ve heard that you had Brendan Gleeson in mind for the role of Bill Hodges early on.

I did. He looks exactly the way I had imagined Hodges would look. The only thing I asked was to make sure he keeps his Irish accent, but put in a line or two about why he has it. My suggestion was he emigrated when he was 17 and found the accent helped him get girls and held onto it. It’s great because it gives him a chance to concentrate on the part and not worry about the accent.

The show is produced and many episodes directed by Jack Bender, with whom you worked on “Under the Dome.” How did this collaboration come about? Did he approach you, or did you go to him?

I can’t remember if he approached me or I approached him, but we wanted to work together again; I loved his work on “Under the Dome.” What impressed me about Jack was he had done so many episodes of “Lost” and he never once felt like he was phoning it in. I thought if I could get him involved, he would direct the majority of the episodes, and he did. (Writers) David E. Kelley was a bonus, and so was Dennis Lehane. I felt like I was in really good hands.

How faithful do you find the adaptation to be and are there any changes you really like?

It isn’t a one-to-one translation, it’s pretty close, but everything that they did really added to it. There’s a part in the book when they discover who the Mercedes Killer is and Beaty goes to a motel room to shave his head. When you see it, I think its episode 8 or 9, what they thought of in place of the motel room is absolutely genius.

They also added the character of Ida, Hodges’ neighbor, played by the amazing Holland Taylor.

She’s terrific. I can’t remember if they ran it by me or not, but when they sent me the first script, I said, “Hmm, she’s not in the book but she’s so smart and straight ahead and what she says is outrageous … yeah, that could be a Stephen king character.” I loved it. It also gives Hodges a chance to talk a little bit and we get to see some of his interior stuff, what makes him tick. Stuff that is more interior in the book. A good writer/director combination sit down and say how do we break this loose and make it interesting for the audience? And they did that.

Is there any work of yours that has yet to be adapted that you’d like to see?

Oh, man. “Lisey’s Story,” I guess. “Lisey’s Story” is my favorite of the books and I would love to see that done, especially now that there’s a kind of openness on the streaming services on TV and even the cable networks. There’s more freedom to do stuff now and when you do a movie from a book, there’s this thing that I call the sitting on a suitcase syndrome. That is where you try to pack in all the clothes at once and the suitcase won’t close, so you just sit on it until it latches. And sometimes when it comes down on the baggage carousel, it busts open and your dirty laundry is everywhere. So it’s tough to take a book that is fully textured and has all the wheels turning and do it in two hours and 10 minutes. But as a TV show you have 10 hours, there’s always the possibility of doing something like “The Handmaid’s Tale,” which is extraordinary.

When you have something adapted, do you like to be really involved? Or do you just say, “Go with God?”

A lot of times I’ll just give it to them and say, “Go with God,” because usually I’m involved with writing a book or sticking close to home with my family. Writing is solitary by nature. But if it’s a project I really like and people involved I really like, then I try to be as involved as I can. I want to be part of a solution, not a part of the problem. I went to the set with “Mr. Mercedes” to see what they were up to and also to do the EPK because I wanted to get on board and say, “Yeah, I’m gonna cheerlead for this.” Because I really like the scripts and I’d seen some rough cuts and was excited by that. And Jack said, “Would you do a cameo?” So I did.

I was going to ask if we could expect a King cameo!

It’s a nonspeaking part and I don’t want to say any more than that, but you’ll see. I’ll be hard to miss, let’s put it that way.

Do you enjoy acting? A lot of people cite your performance in “Creepshow” as memorable.

What they really talk about is the bit I did in “Sons of Anarchy” where I played a crazy guy who cleans up bodies. That was fun. Look, I like to sing in the shower, too, but that doesn’t mean anybody’s ever going to put me on a record. Yes, I like to act, I have a history that goes back to college dramatics. But am I good? When you see Brendan Gleeson work, you know the answer is no. Keep to your day job.

How has your writing process evolved over the years?

There’s more time, but I’m older now I don’t have quite the stamina I used to have but I still work maybe three, four hours a day, seven days a week when I’m working on something. And when I’m not working on something, I don’t know what to do with myself. I just sort of follow my wife around the house until she says, “Don’t you have something to do?”

How involved were you in “It”?

I wasn’t involved at all. I wished them well. Geez, I don’t even think they sent me any swag from that one! But maybe that’s a good thing. I’ve seen it, it’s fabulous.

Is there anything that scares you?

Oh God, yes. Air travel is a big one with me because I feel like I’m not in control. I’m close to 70 now, so I’m worried about basically having the cheese slide off my cracker — Alzheimer’s, dementia, stuff like that. I don’t like bugs, I don’t like bats, I don’t like things that creep and crawl. With the exception of snakes, somehow they don’t really turn my dials. But I’m also afraid of people like Brady Hartsfield, they’re out there. And it crosses my mind every time I do a public event. You think about somebody like Mark David Chapman, and you think maybe somebody’s got a knife out for you. But that’s part of life.

Your fans seem to be mostly intelligent and respectful; have you had any negative encounters?

Most of them are really positive, but it only takes one. When I got out in public, not to be corny, but I feel the love. There’s a sense you made a difference in people’s lives and they want to say thank you for that. Now and then you get a creepy letter. You can’t really control it, all you can hope is you can duck at the right time.