Adam Driver brings a certain gravitas to the Star Wars saga. He’s an accomplished actor (Lena Dunham’s Girls, Jim Jarmusch’s Paterson, Martin Scorsese’s Silence), but, like Alec Guinness before him, he doesn’t condescend to his role in the blockbuster franchise. If anything, he approaches Kylo Ren in the same way he does his art-house roles.

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“There’s big personal things that I find about every character, not just in Star Wars, that you have to make as personal as possible,” he told me. “It’s the big joke about being an actor, that you make everything you’re doing seem like it’s life or death”—including his internal process of becoming Kylo, about which he is circumspect. “The things about that character that I find painful, that I really relate to, I kind of prefer to keep to myself,” he said.

Driver’s in-the-zone solemnity is something his castmates can’t help but take note of. “He’s very moody and intense,” Mark Hamill said. “I remember saying to Adam, ‘I don’t know how you work, or your technique. But, at some point, you were my nephew. I probably bounced you on my knee. I probably babysat for you. There’s that side, and now we’re both estranged from the Skywalker family. All I’m suggesting is, if you’d like, maybe we could go to lunch, we could get together and hang out.’”

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Driver, having his own methods, did not take Hamill up on his offer—“and more power to him,” Hamill said, good-naturedly.

John Boyega, however, is less willing to let matters lie, and feels that sometimes it’s necessary to lighten things up when the mood on the Star Wars set turns too serious. Daisy Ridley, Boyega said, is his frequent co-conspirator. “We collaborate on bringing light to the set and having a good old time,” he told me.

With regard to Driver, Boyega has a specific strategy to try to lure him to the lighter side. “I give Adam hugs randomly, just for no reason,” he said.

“And does he take it?” I asked.

“He just stands there,” Boyega said. “He just waits for me to be done.”