Marc Guggenheim has enjoyed great success the past decade writing for comics ("Amazing Spider-Man," "The Flash"), television ("The Practice," "Brothers & Sisters"), movies ("Green Lantern," "Percy Jackson: Sea of Monsters") and video games ("Call of Duty 3"). But it was a failure -- getting fired from a TV show -- that allowed him to pursue his latest project, his first-ever novel "Overwatch," released this week by Mulholland Books.

Currently serving as executive producer and writer of The CW's hit TV series "Arrow," Guggenheim told CBR News that "Overwatch" is a long gestating passion project and that he's thrilled to finally have it released.

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Blending a Tom Clancy spy novel with a John Grisham legal thriller, "Overwatch" explores the Central Intelligence Agency's Office of General Counsel, which essentially provides government lawyers for spies. The fact that such an office actually exists blew Guggenheim's mind and he hopes readers of his first prose novel are equally excited by the exploits of an outfit that carries "Patria Secura Legali Vigilia" as its modus operandi, which translates to Lawful Vigilance.

Guggenheim also discussed the traits he shares with his leading man Alex Garnett, as well as the book's comic relief, Gerald Jankovick, a character who definitely shares some of the writer's personality traits.

In modern warfare, "overwatch" is the term used to explain when one unit supports another, as well as a Special Ops level in "Call of Duty: Modern Warfare 2." When it comes to who or what is "Overwatch" in terms of his novel, Guggenheim teased that you're going to have to read the book to find out.

CBR News: You've written comic books, television shows and movies, but this week sees the release of your first novel, "Overwatch." Had you considered this story for another medium or was it always going to be a novel?

Marc Guggenheim: "Overwatch" is something that's been kicking around in my notebook for nearly 10 years -- basically, ever since my sister-in-law told me that the CIA had a legal division. I've experimented with this milieu in a variety of mediums, kicking it around as a potential movie, TV show and even as a comic. The advantage of working in all these different mediums is that I have access to a wide variety of different outlets. And "Overwatch" -- or, at least, the arena of "lawyers for spies" -- lent itself, in my mind at least, to a wide variety of executions. That said, because it combines the legal and espionage genres -- genres that, for me, are synonymous with prose -- I feel like the story always wanted to be presented as a novel first.

For the longest time, the problem for me was that it takes a lot longer to write a novel than it does to write a TV pilot, movie or comic book -- by several orders of magnitude. Although I played around with a prose version for several years -- picking up the manuscript from time to time -- I didn't really have the opportunity to write an entire novel until about four years ago when I was fired off of a TV show I was working on and suddenly found myself with a lot of disposable time on my hands. It was my friend and occasional collaborator, Michael Green, who suggested I use that time to write something I wouldn't ordinarily write. And that's when I was reminded of "Overwatch."

You mentioned that writing a novel took way more time than writing for TV, movies or comics but did you enjoy the process?

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Now that the novel is complete, I think I can safely say that I enjoyed the process. Although I've written in several different mediums, prose was absolutely new to me and there was a huge learning curve to conquer. In many ways, it felt like I was getting back to my roots. Long before I got involved in creative writing, I was very much what I would describe as an "expository" writer -- I'd write essays and whatnot and then, later, I'd write legal briefs and arguments when I was practicing law. For me, all that writing was about stringing word together in an aesthetically-pleasing way. Although I wasn't telling stories, I was very focused on how the words sounded together, what the rhythm of the writing was. Those were skills -- and a love -- working in prose afforded me the opportunity to revisit.

At the same time, I enjoyed being the sole author, the lone person responsible for the entire entertainment experience. I love the collaboration involved in all the other mediums I work in, but it was fun to change it up for a bit and be responsible for the whole enchilada. There's nowhere you can hide in prose. You can't blame the actors or the artist or the director. It's all you. That's as exciting as it is terrifying.

I also have to say that the folks at Mulholland Books made the process remarkably enjoyable. They really carried me over that learning curve I mentioned. Despite being a voracious reader, reading novels doesn't fully prepare you for writing one. I had so much to learn I didn't even know what I didn't know. Hopefully, my ignorance has been rendered invisible by the time of publication, but that's all thanks to the folks at Mulholland and my amazing assistant Grace DeVoll, who was absolutely indispensable.

In the media release announcing "Overwatch," Tom Clancy and John Grisham are listed as authors of comparable books. What separates "Overwatch" from other thrillers?

If everything works as planned, the combination of two different genres -- legal and espionage -- creates a brand new kind of book. My hope for "Overwatch" is that it's a Reese's Peanut Butter Cup of a novel -- two great tastes that taste great together, something you haven't experienced before. In writing the book, I took care to craft a story that had as much espionage in it as legal thriller and vice versa. My intention wasn't to write a Tom Clancy thriller or a John Grisham novel, but rather, craft the kind of story that you might get if Grisham and Clancy had actually collaborated on a novel. That is something I've never seen before and I hope that readers have never seen it before, either -- but are interested to.

Who or what is the titular Overwatch?

Ah, well that's the central mystery of the novel. I don't want to spoil too much, obviously. I will say this: I'm fascinated by certain themes as a writer. One is the axiom that the villain is the hero of his/her/their own story. No one who is evil actually thinks that they're evil. They operate from a point of view and according to motives that they believe are legitimate and justified. I find that kind of fascinating and I think it makes for villains who are fascinating, who are more than two-dimensional bad guys.

As a former attorney, I'm also interested in the related issue of justice, specifically, the occasional conflict between law and justice. Sometimes what is legal isn't right -- and sometimes what is just isn't legal. That dichotomy is one of the things I find fascinating about the CIA's Office of General Counsel, the milieu where the novel is set. These men and women are, essentially, "in-house counsel for spies." Their job is to practice law in a world that is extremely grey. In such circumstances, what is justice? What is legal?

What can you tell us about your leading man, Alex Garnett?

Alex is essentially a normal guy. I'm tempted to characterize him as an "everyman." In one sense, that's true. He's not an ass-kicking action hero type like you would find in most thrillers. He's a character more in the vein of Jack Ryan or Joe Turner, who is Robert Redford's character in "Three Days of the Condor." When he gets shot at, he's afraid for his life. When he punches someone, his knuckles bleed. He is very much in over his head.

At the same time, what keeps him from being average is his legal acumen. He's actually a brilliant attorney with a capacity to think outside the box. Unfortunately for him, however, he's grown up in his father's shadow. His father is even more brilliant than he is. And far more accomplished. Alex's father is a former Solicitor General and Chief of Staff to two presidents. Although Alex has followed his father into law, there's a rebellious -- and self-destructive -- side to him that prevents him from being as accomplished as his dad because he keeps floating from job to job to job.

Alex is a lawyer, which is familiar territory for you. Was he modeled after someone you know? If not, what was his inspiration?

Interesting question. I suppose my fear is that, on some level, the inspiration for Alex is me. I don't think that's the case, but at the same time, I can't point to anyone in my life he's modeled after. Rather, Alex is an amalgam of traits that I wanted to write about. I was drawn -- for some reason -- to a protagonist, who has a special skill -- in Alex's case, law -- but can't seem to get out of his own way, can't seem to get his shit together. That, of course, raised the question of why and I tumbled to the idea that he was living in a parent's shadow. I started to be intrigued by telling a father/son story, particularly one set within the corridors of power in Washington, D.C. and Langley, Virginia. I'll leave it to readers and critics to speculate on whether I'm working out my own issues through Alex.

And what about the "neurotic hacker" that Alex teams up with to unravel the conspiracy in "Overwatch"?

Well, if there's a character in "Overwatch" that is modeled after me, it's probably Gerald Jankovick, a geek who is neurotic and anxious. I'm mostly joking. Kinda. [Laughs] Gerald, you could say, is the comic relief in "Overwatch." The character serves as a mechanism for several important plot points, but the key to making that process invisible, hopefully, to the reader lay in making Gerald interesting and compelling in his own right. I was interested in writing a character that's neck-deep in this vast conspiracy and is practically screaming, "Screw this! I'm going to Aruba." That's the kind of character you don't see in many thrillers. In most thrillers, the protagonists are racing head-first into trouble. Gerald's the opposite. His first instinct is to run the other way. Actually, his first instinct is to pop a Xanax -- then run the other way.

Why do you think the general public and readers specifically remain fascinated by homeland security, the CIA and other intelligence gathering organizations?

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That's a great question. Obviously, intelligence agencies by their nature are mysterious and their workings generally hidden from view. Just as obvious is the propensity for people to be understandably curious about the inner workings of those black boxes. These agencies are real-life secret clubs, whose inner workings are, by design and by necessity, kept out of public view. In writing "Overwatch," I was extremely fortunate to get the assistance of a former non-official cover officer of the CIA. One of the things I love about Tom Clancy's novels is the "inside baseball" nature of them. I like being educated even while I'm being entertained, and I like feeling like I'm getting a peek behind the curtain. That's something that I really wanted to make sure I brought to the novel, particularly where the CIA is concerned.

If "Overwatch" proves successful, do you have plans for future novels set in this world with these characters?

About halfway through writing the novel, I started to get ideas for what might happen with Alex and this world next. It's always dangerous to hang your hopes on the success of something that has yet to be released, but I couldn't help the ideas from coming. I truly hope I get to return to Alex's life after the publication of this novel. There are some very interesting places I plan to take him.

And what about opportunities to translate it to other media where you have so many existing connections, be it comics, television or feature film?

That's always the icing on the cake whenever you develop a new piece of intellectual property. I could see incarnations of this world in any of the other mediums I've worked in. As I said, I'd kicked around a bunch of different iterations when developing the original story, so in many ways taking "Overwatch" to TV, film and/or comics would be like coming full circle.

"Overwatch" is on sale now from Mullholland Books. Fans can meet Marc Guggenheim during a reading and signing event at the Santa Monica Barnes & Noble Friday, April 18