A video game changed the life of Wilbert Roget, II.

Roget was raised in Philadelphia, and began receiving classical piano training at the age of 4. Gaming was not part of his childhood, until one day he saw a TV ad for Final Fantasy VII, which was released when Roget was in middle school.

“It was like an ad for a movie. I thought it was the coolest thing ever,” Roget recalls. “I saved up and got a PlayStation and fell in love with it.”

It wasn’t the gameplay or plot that was life-changing for Roget. It was the music that played in the background. Unbeknownst to the teenage Roget at the time, the score was written by Nobuo Uemastu, a legendary composer who has been called “the Beethoven of video game music.” What the formally trained Roget did know is that he loved what he heard.

“Yes, this is what I want to do,” he remembers thinking. “I didn’t want to do the classical piano thing. I wanted to write game scores.”

With Final Fantasy and other games, he began using a hand-held recorder to tape different sections of the music so he could transcribe it and study what the composers were doing. Advancing to new levels meant, for Roget, new songs to explore.

“That taught me about arrangement and form and eventually about melody, as well,” he says. “It was that classic Nineties JRPG [Japanese Role Playing Game] music that started it all for me.”

Today, Roget is reaching millions of gamers with scores of his own—most recently as the composer on the blockbuster Call of Duty: WWII, which brought in half-a-billion dollars in its first three days of sales, according to publisher Activision.

The 33-year-old Roget, who lives in Seattle’s Wallingford neighborhood, recognizes that gamers aren’t flocking to the latest Call of Duty game for its score. Yet his work plays a central role in how users experience the campaign, which follows Army First Class Ronald “Red” Daniels and his platoon in the 1st Infantry Division.

The score draws off two major themes, Roget says. One theme is what he calls, appropriately, the “call to duty,” a “big, brassy” sound that speaks to the “bravery and self-sacrifice” of battle. The other theme is what he calls the “haze of war,” more dissonant and sinister. He says the game-makers at Sledgehammer made clear to him that they did not want a score that sounded like it was straight out of 1940s war epic. Instead they wanted something modern and humanistic. He says he tried to get into the head of Daniels, a Texan who’d never been overseas before. “I’m going off to some far-off continent I’ve never been to before. What does this mean to him, what do these friendships mean to him?

“I wrote in the first person,” he said. “I didn’t have room for embellishment. It had to be much closer, and grittier, and it got darker as the story progressed.”

Even from the trailer, one gleans the heroic-but-dark tone Roget’s music helps create for the game. (Listen above for a selection of tracks from the score, via Roget’s Soundcloud channel,.)

Call of Duty: WWII represents a return to form for the franchise. Having started out as a WWII shooter, the game has expanded its universe in recent releases, with 2016’s release, Call of Duty: Infinite Warfare, taking place in outer space — with many fans grating at the extra-terrestrial direction the series was taking.

This game to has received generally, though not unanimously, positive reviews. Just as with the huge sales, Roget knows his work isn’t the first thing reviewers notice, but hopes his work contributes to the experience.

“You’re not at the forefront,” he says of being a game composer. “You’re supporting the action. They hire a composer because they want to make the game that much more fun, more memorable.”

Roget — who also has composer credits on AAA titles Star Wars: The Old Republic, Lara Croft and the Temple of Osiris, and others — moved to Seattle two-and-a-half years ago and has been impressed by the city’s gaming industry, especially as it pertains to his field of work.

“I would definitely say that Seattle has the best game audio community in the world,” he says. “We have a large community, and it’s quite diverse. You have the AAA people, but you also have indies.”

In addition, the city has a robust music community that Roget—being at the nexus of art and tech—appreciates. “You can’t throw a brick out a window without hitting a saxophonist in this town,” he says.