In late 2020, Kai Alexander received an e-mail from his agent that was both opportune and frightening. Its subject line read: “Untitled Apple TV Plus miniseries with Steven Spielberg and Tom Hanks.” He clicked on the e-mail and learned that the show, Masters of the Air—which premieres on Apple TV+ this Friday—is based on Donald L. Miller’s nonfiction book about the 100th Bomb Group, an air-force unit during World War II. Alexander imagined a clean-cut, muscular, all-American actor for the role. He took a look at his slim frame and shoulder-length ginger locks in the mirror and said to himself, “Oh God, this is all wrong. This is not it.”

Alexander, a 26-year-old actor from the West Midlands, in England, tied his hair back for his first audition and was sure the casting team wouldn’t give him a callback. But a few months later, he was summoned to a two-week basic military training course in the outskirts of London with the 40 other cast members of Masters of the Air, including Austin Butler, Barry Keoghan, and Callum Turner.