“I tell you, if I had not been cast in Star Wars, I would have been there first day, first show,” Mark Hamill told me when I sat down with him earlier this year for an interview at his home in Malibu. And whoosh! Off he went into an ornately detailed remembrance-reverie of a youth spent reading Famous Monsters of Filmland magazine, getting spooked by the stop-motion adventure films of Ray Harryhausen, worshipping Peanuts creator Charles Schulz, and collecting Superman comic books.

This didn’t square with my childhood impression of Hamill. In 1977, when he first rose to fame, he was the Star Wars phenomenon’s heroic prettyboy; he looked like a junior-tennis star who probably had a Björn Borg poster on his wall and no interior life. But, as it turns out, Hamill was a geek all along—something that has become more evident in recent years via his showy voice-acting roles in various animated series and his chatty, agreeable appearances at Star Wars events.

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And he’s delightful company: a generous-spirited, and therefore hypothetical, version of The Simpsons’ Comic Book Guy. One room of his house is a veritable Android’s Dungeon of collectibles, from Beatles memorabilia to vintage 1960s board games (The Exciting New Game of The Kennedys; Oy Vey!, “The Game Where You Become a Jewish Mother”) to, yes, Simpsons figurines.

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Hamill regards the Star Wars franchise from an unusual double perspective: as both a central figure in it and as a grown-up version of his geeky childhood self. As the actor who plays Luke Skywalker, he is privy to fascinating inside information; he told me that, in an earlier version of the script for The Force Awakens, “The first thing you see when they pan down after the crawl is a severed hand holding a lightsaber that is flying through space”—which is to say, A) the hand of Luke’s that Darth Vader sliced off in The Empire Strikes Back; and B) the family-heirloom lightsaber that Rey eventually offers to Luke at the conclusion of The Force Awakens. Yet as a regular-guy Star Wars fanatic, Hamill approaches the movies like any other obsessive, drawing up his own fan-fiction scenarios that he wishes those darned filmmakers would take up.