Superhero fans around the globe are gearing up for Friday’s release of “Avengers: Age of Ultron” and the cinematic return of Iron Man, Black Widow, Thor, Hawkeye and the Hulk. But for every tent-pole entertainment it delivers, Marvel Comics, like its competitor DC Comics, creates products that fly below the radar of many fans but still tie in to their big-budget movies and monthly comics: children’s books, novelizations, video games, reference works and much more.

Those additional stories don’t write themselves. When comics companies or film studios need colorful superhero-related prose in a hurry, they often turn to South Portland resident Alex Irvine.

Irvine, 46, has written novelizations of properties such as “Tintin,” “Transformers,” “Iron Man 2” and TV’s “Supernatural.” He has written comics starring Daredevil and Hellstorm (Son of Satan), and he has scripted games like Marvel Avengers Alliance, Marvel War of Heroes, and Marvel PuzzleQuest – which together have more than 75 million players. When he finds spare time, Irvine also writes short stories and his own award-winning stand-alone novels, including “Buyout,” “The Narrows” and “A Scattering of Jades.”

A native of Michigan, Irvine attended graduate school at the University of Maine at Orono. Since then, he has worked as a reporter, a college professor and now as a full-time writer. And when another action blockbuster arrives at the multiplex, movie studios and comics publishers often gear up for a storm of spin-off merchandise by getting in touch with Irvine.

“With something on the scale of ‘The Avengers,'(the associated merchandise is) pretty much everything you can think of,” Irvine said. “There are tie-in novels, usually for adults and kids. Sometimes the publishing side of Marvel does comics tie-ins, although they tend to try to keep the cinematic and comic book universes apart.”

Irvine’s “Phase One” books, written for 8- to 12-year-olds, spotlight individual members of the “Cinematic Universe” Avengers.

The films also have a big effect on the online games that involve Marvel’s deep roster of heroes and villains. Launched on Facebook in 2012, when the first movie opened, the Avengers Alliance game casts new players as agents of S.H.I.E.L.D who must help Nick Fury keep New York City safe from an unknown threat. The role-playing experience is enhanced by social media, which allows players to recruit their friends and team up against the bad guys as they play on Facebook, phones, tablets and other devices.

“For Avenger’s Alliance, there’s new content coming out all the time,” Irvine said. “I’m always writing new missions and new story chapters.”

Elements of “Age of Ultron” will play some part in the action. Irvine said. “There is usually some time-limited new mission to play through that touches on some of the movie plots and amps up interest. There will be rewards in the games, which you can only get during that time frame, that have something to do with the movie.”

Irvine said that he enjoys the new game space afforded by various devices. “Especially mobile, because phones are changing so fast. From month to month, as you get a new idea about what a game might look like, the technology has changed underneath you.”

Irvine started writing comics thanks to New York City’s KGB Bar, where he read from his 2005 novel, “The Narrows,” one night. Irvine struck up a conversation with a friend of a friend who worked for Marvel, and that led to a comics assignment. That gig brought the opportunity to write his first movie tie-in, “Iron Man 2,” in 2010.

Preparation for writing a movie tie-in novel can involve in-depth research or be more of a seat-of-your-pants affair. Sometimes Irvine is able to speak with the film creators directly. Such was the case with his novelization of the “giant monsters on a rampage” saga of 2013, “Pacific Rim.”

Irvine said, “I met with (director) Guillermo del Toro and we talked over stuff he couldn’t get in the movie but were still parts of the story he wanted to tell. That helped me figure out the best way to go forward with the book. But every studio has a different practice.”

Asked who his favorite heroes are, Irvine said, “Iron Man’s always fun. Once you get the snarky, know-it-all tone going, you can riff on that for a long time. He’s a blast.”

The Guardians of the Galaxy, due to be revisited by Irvine later this summer in a new tie-in novel, are also reportedly fun to work with, as is Thor.

How long does Irvine think global audiences will remain enamored of comic book heroes and desire a steady stream of new movies and their associated tie-ins?

“I think the novelty of it is going to wear off sooner or later, if it hasn’t already,” he said. “But what I think is going to happen is that superhero movies will become just a part of the film landscape. Superhero stories are a lot of the time about spectacle, and that’s one thing that big-budget Hollywood movies do well.”

Over the last year, Irvine said he has been able to re-balance his schedule and get back into writing his own fiction again. At the time of this interview, he was transcribing a new stand-alone novel from his handwritten notebooks into his laptop.

South Portland is at a remove from the hubs of the entertainment industry, but it’s possible to maintain a comics-related career from coastal Maine.

Irvine said, “There are times when it would be useful to be in New York or L.A. I think that’s more true for TV and film, though also true for games. People ask me all the time, ‘How do you keep your writing career going in Maine?’ I think if you write books people like and you’re a professional to work with, people are going to want to work with you. That’s going to be true anywhere.”

Michael Berry is a freelance writer.