(CNN) -- The main character in Nick Harkaway's new novel, "Tigerman," is a British solider who becomes a self-made superhero.
But all Sgt. Lester Ferris really wants to be is "Dad."
"Tigerman" is about geopolitics, environmental disaster and the 24-hour news culture. But, at its core, Harkaways says "Tigerman" is a story about fatherhood and the "power of paternal and filial love."
It's not your typical father-son story, says Harkaway, a married father of two and the son of legendary spy novelist John le Carré. But, "something about the nature of guns and the similarities between being an NCO (noncommissioned officer) and a parent," combined with revelations in the British press in 2010 about rendition, led Harkaway to start writing.
The book deals with darker themes of justice and vengeance, similar to another hero with father issues, "Batman." Despite the comic book overtones and its location on a fictional island scheduled by NATO for demolition, Harkaway says he tried to keep the story grounded in reality.
In other words, no laws of physics are broken, he says. "It's the most real, in a way, of the books I've written."
After years of dodging enemy fire in Afghanistan and Iraq, the main character Ferris is sent to the fictional island of Mancreu, a "spit of land" in the Arabian Sea, to serve as the last representative of Her Majesty's government.
On Mancreu, Ferris meets a nameless, streetwise boy raised on comic books, action movies and video games. His self-taught English is a mish-mash of "leetspeak" -- the language of the elite -- riddled with pop-culture references and Internet slang.
Most importantly, the boy may be an orphan. Ferris is also a man without a family. When he and the boy bond over their mutual love of comic books and afternoon tea, Ferris starts to imagine life as a father. Ferris' hopes bloom into a plan to adopt the boy (if he's willing) and forge a future together.
But the sergeant and the boy face a deadline for their would-be family. After years of ecological abuse, Mancreu has become an environmental disaster. NATO has earmarked the island for destruction. Residents who can afford it are "Leaving" with a capital "L." Others are hanging on and facing eventual evacuation.
With an end date looming, anarchy and lawlessness spread across the island, think Casablanca, only with "discharge clouds" of toxic pollution.
When a group of gun-toting thugs kills a mutual friend, the boy inspires Ferris to become "Tigerman," part vigilante, part myth and "full of win," as the boy says.
The sergeant dons a homemade mask, body armor and utility belt to battle bad guys and hopefully convince the boy to become his son when the dust settles.
Comic book fans will recognize elements of the Caped Crusader, with Ferris playfully referring to the boy as "Robin" in the book.
Harkaway names "Dark Knight" and "Sandman" among his childhood favorites. But "Tigerman" isn't so much his version of "Batman" as it is his take "on me, or any of us, shoved into being a costumed hero," he says.
"Batman is one of a small number of characters who get the title 'superhero' despite having no actual superpowers. Although I've heard it said that he has the best superpower of all, that of being ridiculously rich in a world where technology can make you a god."
Harkaway is the author of two previous genre-bending and critically-acclaimed novels, "The Gone-Away World" and "Angelmaker." Despite his famous lineage, he says he doesn't pattern his work after his famous father.
"We haven't spent a lot of time consciously talking about writing in a master-student kind of way, but we have similar concerns, ethical worries, (and) geopolitical perceptions in some areas. I like to think that my thought influences his in some areas, too."
For now, Harkaway is already at work on his next novel about "semiotics, murder, alchemy, sharks, banking, game design and the surveillance state," he said.
He's also making time for fatherhood, something he describes as "the best, and the most extreme" adventure.