'Gray Man' Author Mark Greaney Talks 'Sierra Six' and Why He's Excited About the Upcoming Movie

With 19 novels to his credit, it's hard to fathom that Mark Greaney's first book was published in 2009. Since then, he's worked at a furious pace to deliver seven Jack Ryan novels (three written with Tom Clancy before the author's death), one standalone novel and 11 novels about a mysterious operative called the Gray Man.

"Sierra Six" is the latest Gray Man novel, published in February 2022, just a few months before a Netflix movie starring Ryan Gosling and Chris Evans will be released by the streaming service. "The Gray Man" was directed by Joe and Anthony Russo, the team behind the most successful Marvel movies.

"Sierra Six" tells two stories, one set in the present day and the other that flashes back 12 years to tell the story of Court Gentry's struggles to integrate into a team after he's assigned to the Golf Sierra spec-ops unit within the CIA's Special Activities Division. When a current mission in Algeria goes wrong, Gentry discovers that he's on an assignment tied to a disastrous Golf Sierra mission in Pakistan. Greaney seamlessly switches back and forth between timelines, and each new chapter reveals more about what really happened back then and the threat the world faces now.

Gentry was raised in Florida at his father's weapons training school and never served in the military. How he first became a lone-wolf operative is at the core of Greaney's first novel, "The Gray Man," and likely will be revealed in the upcoming movie. Every novel features a disconnect between Gentry and the veterans or active-duty military he's assigned (read: forced) to work with. That conflict keeps the books interesting, and the success of the Gray Man series has continued to grow over the past decade.

Greaney talked with Military.com about "Sierra Six," how he became a writer, what it was like to work with and learn from Clancy and why he's excited about the upcoming movie.

Military.com: "Sierra Six" seems like a two-for-one novel, with two distinct stories woven together into one book. Is it the longest Gray Man novel so far?

Mark Greaney: "It's pretty close at 165,000 words all done. I kind of see it as two 80,000-word novels, woven together. That wasn't even really by design, but that's just the way it turned out."

Military.com: With so much backstory in "Sierra Six," this one seems like it might be a good place for new readers to start reading about the Gray Man.

Mark Greaney: "I like to think of all my books as standalone, because I do explain who's who and always allude to histories and Court Gentry's past. But this one, there's definitely more of that. Half of this book takes place 12 years in the past, so this one's a good place for somebody to jump in."

Military.com: What's always been fascinating about Court Gentry to me is that he's almost an anti-military character. He's never served in the military, and he irritates all the veterans he works with on the ops teams. How did you conceive of an ace special ops warrior with zero military experience?

Mark Greaney: "I first wrote the Gray Man in 2007. I felt like there was a lot of stuff about military people in the military. I wanted to make him CIA, but without a military background. I wanted him to be different from the other people around him. So he was like that from the beginning.

"I obviously do a lot of research on the military and with people in the military, and the military is featured in every single Gray Man book in one way or another. But I always want my protagonist to be an outsider to the events going on around him. That never has been more true than in 'Sierra Six,' where you actually see him with a paramilitary team trying to integrate and fit in.

"Gentry is trained up as just an operations officer, but he came into the agency with the skills that he'd learned through law enforcement and military training at his father's firearm school. He comes into the agency with all this knowledge and got two years of very intensive training before they put him out in the field.

"In 'Sierra Six,' he's folded into this unit where everybody else is military. I'm sure that pretty much everybody in Ground Branch is military. That contrast makes both sides interesting. It's interesting for someone not in the military to see some of the military culture. And then it's probably interesting to look at these guys with their background looking at somebody like Court coming in and seeing him like he has a unicorn horn on his forehead."

Military.com: Publishers have recently been pushing military thrillers written by guys who served. You're obviously one of the most successful writers in that field, and you're a guy who didn't serve.

Mark Greaney: "The first thriller I ever bought in my life was Tom Clancy's novel 'Patriot Games,' back in the '80s. Tom wasn't able to serve in the military, either. Maybe that gave me a little bit of hope. The first several years, I was just a reader. I wasn't trying to become a writer, but then I got an idea for a story and piddled with it. I feel like I've learned my craft by doing things wrong for almost 20 years until I got published. I was making lots of mistakes, and then recognizing them, and then making fewer and fewer.

"When it comes to the military, I get stuff wrong. But I also have a cadre of people that I will reach out to about one thing or another. 'Sierra Six' is my 21st published novel since 2009. It's funny that, as I get further along into my career, I do find that the technical aspects of it are a little bit less important. Because I want to create the tension and tell the story the way I want to tell it.

"There are things that happen in books, where I'm like, 'Yeah, I don't think this could really happen.' I could dig into the background and find the details. But you know, this thing needs to happen for the story, because I'm trying to elicit this emotion from the reader on this page.

"The best way to do that is for all the satellite reception to be disabled for the next 90 minutes so the team can't see what's going on. Is there a way I could figure out how to do that and technically explain that? Probably, but I want to just say it happened because it's important for the story. So that's what I do."

Military.com: That's the point where you veer away from your Tom Clancy roots. Tom loved to explain exactly how everything worked.

Mark Greaney: "You're absolutely right. I really think it's a different day. And I don't know that that type of techno thriller would work today, and Tom might totally agree if he was still around. In 'Sum of All Fears,' he has a six-page explanation of a nuclear detonation. I would probably just say, 'Boom,' not that there's anything wrong with what he does. He's obviously a master.

"Tom Clancy novels are what got me interested and kept me interested. It's just that I feel like it's a different day and age. Some current writers are a little more technical than others, but I don't think anyone's quite as technical as Tom was back in the 'Red Storm Rising' days.

Military.com: You're obviously someone who knows a bit about how Tom Clancy thought, since you co-authored a few Jack Ryan novels with the master. How did you come to work with Clancy?

Mark Greaney: "​​Way back in 2011, my agent called me and asked if I was sitting down, because the publisher was considering me to work with Tom. At that point. I've only had two published novels. Both of them were little mass-market paperbacks. One was a Gray Man book, which did really well and sold to Hollywood. But I was certainly not any sort of a household name.

"I certainly didn't merit writing with Tom Clancy at that stage in my career, but they gave me the opportunity. I actually tried out and wrote 30 pages or something, as if we're right in the middle of a Tom Clancy novel, just to show that I knew who the characters were and how they talk to one another and whatnot.

"They had me go up to Baltimore and meet Tom. We did that first book called 'Locked On.' We had literally just finished our third novel, 'Command Authority,' the last week of September, and Tom died the first week of October 2013. That book came out in December.

"Pretty quickly, the family asked me if I would continue the Jack Ryan series. So I wrote four more after Tom's passing. So I ended up doing seven novels in six years, three with Tom and four on my own. That was the best training, and obviously, it was incredible for my career as far as getting my name out there. So it was a good experience all around.

"The work was very fast-paced, because I was also writing other books. Tom Clancy novels are big novels, so a lot of these were 200,000-word books. And then I was trying to crank out another 150,000-word book in the same year. So it was a tough time, but I'm so glad it happened."

Military.com: "How are you so productive? That's two books a year, right?

Mark Greaney: My joke (and it's not really a joke) is that I'm so productive, because I signed contracts that say that I will write these books. There's that moment when you sign the contract, and you're feeling really happy. And then six or nine months later, you're like, 'Oh, my gosh, what have I agreed to do? I'm so deep in the weeds.' And that's always the case.

"I worry now because there's a film coming out made from one of my books, and I've got two novels coming out this year. Now I have a family and all this other stuff, but I've still committed to write the same number of words that I wrote when I lived alone and had no other distraction.

"Every year I have to manage a little bit better. I don't have problems with big ideas for stories, but after 20-something books, sometimes it's hard to come up with a new scenario that you haven't written about before. I struggle with coming up with new fresh stuff.

"The best antidote is to do the research, the location research or the research with the military. I got to fly backseat in an F/18 with the Naval Reserve last fall. That was incredible research and fodder for a future book. As long as I keep doing that, I think I can stay prolific."

Military.com: The Gray Man has taken a long and winding road to the screen. Now you've finally got a movie coming out this summer. What's that experience been like?

Mark Greaney: "I'll start out by saying that I'm a glass half-full person overall. Now people are saying, 'Hey, this thing has been in Hollywood for 13 years. Isn't it depressing that it took that long to get the film out?' No. If I was on my deathbed and they'd made a film out of one of my books, I'm still a super lucky person.

“It wasn't that it took so long that bugged me. There were a few false starts; there were a few points where I actually got hopeful for it being made. When I originally sold the option to Hollywood way back in 2009, I didn't think anything would come from it, other than I get paid a little bit of money, and I could sort of use it as something to promote my book because Hollywood is considering making a film.

"But it did get close a few times over the years. And I really haven't been that involved, other than watching it bounce around like a basketball between Hollywood studios. Sony had it a few and the Russo Brothers, who are the directors of a lot of the Marvel movies like 'Avengers: Endgame' and 'Captain America: The Winter Soldier,' wanted to direct it and to write the script. They had me come out to California and spend some time with them. And then Joe Russo wrote the screenplay, which was fantastic. And then the movie kind of died on the vine at Sony.

“Then it was rekindled at Netflix, and the Russos were attached again. Joe worked on the script again, and more screenwriters worked on it. They sent me the shooting script last year right as they started filming, and I was blown away by it. So I'm super excited that the movie is actually finally coming to pass."

Military.com: Prime Video has enjoyed some success by adapting Michael Connelly's Harry Bosch novels, Lee Child's Jack Reacher novels and Jack Carr's James Reece novels as series instead of movies. Obviously, making a movie is a different approach. How much will the movie alter the first novel?

Mark Greaney: "They make quite a few changes. They also add things that take place in other Gray Man books, because they're trying to establish this as a franchise to make more movies based on other books. One of the ways to make that work as a story arc for a film franchise is adding some characters in 'The Gray Man' movie who don't come in till book three or book five of the series, but are kind of integral to the story that they're telling you in the movie.

"So the film follows the book about 70%, something like that, which is all anyone can hope for. I've already dealt with fans on social media who are like, saying, 'Well,they better not do this, or they better not do that.' And I just kind of roll my eyes a little bit. The directors are creative people just like the author of the original work. They're not engineers who look at a page of text and say, 'Alright, how do we replicate this perfectly?' They are putting their spin and their ideas into it as well. I'm fine with that. They have the character and they have the story right.

"There was one screenplay that was written for ‘The Gray Man’ several years back by another studio. Honestly, if I went to the theater and saw the movie, and it had a different title, I would not even recognize it as a book that I had anything to do with. It was that different. So I'm really happy with the end result of this new movie.”

Military.com: What's next for you?

Mark Greaney: "I have a book called 'Armored,' which will be out July 5. It's about civilian military contractors in Mexico and the drug cartel land of the Sierra Madre Mountains. And I've actually sold this one to Hollywood as well. Sony Pictures has that with Michael Bay to produce."

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