It turns out that this was far from the 64-year-old writer's first involvement with Fox. "Back in '98, '99, when I was vp editorial director at Marvel, I had to write a memo to Fox explaining how to make the X-Men relevant to the audience as a film-story concept," he tells THR. "The project was just this side of turnaround, and apparently my memo tipped the scales in its favor. Back then, that felt totally great — and the success of the film illustrated the potential a properly done comic book project could have on the movie market."

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The success of the original X-Men movie led to many happy memories for Claremont. "It's more fun than I can tell to find oneself shoulder to shoulder with performers and filmmakers I've enjoyed for years, especially when they're bringing my characters and stores to life," he says, citing the chance to spend time with Bryan Singer and Hugh Jackman on the set of Days of Future Past and pitching an X-Men movie to James Cameron alongside Stan Lee as two particularly fondly remembered moments.

Humble about his own experience — asked about advice he has for other writers, he demurs, "I'm still trying to figure things out myself" — he's more open when talking about the potential future for the X-Men movie franchise and where he'd like to take it given the chance. "We have all these superb actors, playing all these great characters — as both writer and audience, I just want to find ways to bring them to cinematic life as richly as they deserve and, in the process, leave the audience hungry for more," he says, calling X-Men "a franchise with the depth of character and concept that make it valid as film concepts or TV concepts, as ongoing series or limited series, on network or perhaps cable."

Ask him for possible new directions for the franchise, and he has many suggestions. "With New Mutants, you can appeal to kids and explore the tensions and pressures of young mutants trying to get a handle on their powers and their lives," he offers. "With Excalibur, you have the option of leaping literally out of this world — I mean, they have a pan-dimensional, interstellar train, for Heaven's sake — to other star systems or possibly even other dimensions."

Outside of the X-Men, he says that classic British comic character Dan Dare remains a favorite that he'd love to see translated onto the screen, along with French comic series Valerian. But his heart belongs to Marvel's mutant heroes, and what they can offer everyone. "You don't have to play to the traditional cliche of folks in skintight suits," he says. "You can take the out-of-this-world element of the concept and present it in terms that make the conflicts and characters meaningful on personal levels to the mainstream viewing audience. Where it comes to the X-Men family, as far as I'm concerned, the sky isn't the limit; it's just the first leg of a wonderful adventure."

Claremont is one of The Hollywood Reporter's Hollywood's 5 Most Powerful Comics Writers for 2014. Check out the rest of the list, including Robert Kirkman and Geoff Johns, here.