Mark Hamill's role as Luke Skywalker in George Lucas's 1977 film Star Wars catapulted the young actor and his co-stars to stardom. However, thanks to not having the full script and a confusing screen test with Harrison Ford, Hamill wasn't aware he was reading for the film's lead; instead, the iconic actor believed he'd be playing Han Solo's sidekick.

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Asked in a recent interview with official Star Wars website about whether the influence of classic movies and comic books drew Hamill to Star Wars, the actor responded that he actually wasn't certain at first whether or not the movie was serious, and talked about his confusion regarding the role.

"I got that part without having read the entire script," Hamill said. "I got a scene. First of all, there was a cattle call, where everybody in town that's the right age goes in and they look at your size, your height, your looks, your this, your that. And you talk back and forth. They interview you, you don't really hear them talk about the movie. And then you get the scene, you do the scene, and I'm trying to figure out, 'Wait a second. Is this straightforward? Is it kind of a parody or an ironic sendup?' I tested with Harrison [Ford] and I couldn't [figure it out]. George [Lucas] just said, 'Well, look, let's just do it and we'll talk about it later.' Which is classic George, because you learn later that he says, 'Let's just do it,' and then he never talks about it later."

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It wasn't until he read the script at home that he discovered he would actually be playing the film's lead character, not Ford.

"But when I finally got the part and they said they were sending the script over, I was living by myself in a one-bedroom on the beach in Malibu," Hamill recalled. "It was before I was married. And I get the script and I sit down, and I'll never forget the chair I was sitting in, facing the ocean. I open the title page and it says, 'The Adventures of Luke Starkiller, as Taken from the Journal of the Whills, Saga Number One: The Star Wars.' And I thought, 'Wait a second…' Because when I tested, I figured Harrison's a leading man. So I thought, 'I'm playing his sidekick, right?' Reading it, I'm going, 'Wait a second. Wasn't I reading for Luke Starkiller? This can't be right.' Anyway, I started reading it and you can imagine. I mean, 'A long time ago in a galaxy far, far away.' Then you read the crawl and you're right in the action. It's just such an economical example of storytelling."

Prior to Star Wars, Ford had already worked with Lucas on 1973's American Graffiti as well as Francis Ford Coppola's 1974 film The Conversation. Comparatively, Hamill had mostly worked on TV shows and didn't have much big-screen experience.

The title for the script that Hamill provides in the interview corresponds to the film's fourth draft. Eventually, Lucas would change the name of his main character, Luke Starkiller, to Luke Skywalker.

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Hamill will next appear as Luke Skywalker in Star Wars: The Last Jedi. Arriving Dec. 15, that film also stars Carrie Fisher, Adam Driver, Daisy Ridley, John Boyega, Oscar Isaac, Lupita Nyong’o, Domhnall Gleeson, Anthony Daniels, Gwendoline Christie, Andy Serkis, Benicio del Toro, Laura Dern and Kelly Marie Tran.