In a New York Times interview, Hamill says he first heard about episodes 7, 8 and 9 in the saga in 2012. At a lunch, creator George Lucas told Hamill and co-star Carrie Fisher their old roles could be theirs again. It didn't take Fisher long to agree.
"I was completely stunned," Hamill said of the news. "Carrie, not a minute went by -- she slapped the table and goes, 'I'm in!' I said, 'Carrie, poker face!'"
But Hamill had doubts.
"I thought, why mess with it?" he told the Times. "No one wants to see the 50-, 60-, 70-year-old versions of us, running around,."
He assumed that Ford, who's now 75, would feel the same way. "He's too old and too rich and too cranky," Hamill said. "He's not going to do this."
What's that Han Solo once said about "never tell me the odds?" Ford, surprisingly, agreed -- and now Hamill felt he had no choice.
"Can you imagine if I was the only one to say no?" he said. "I'd be the most hated man in nerd-dom."
Ford wasn't the only co-star who helped Luke find the Force. Hamill said the late Fisher once noticed he wasn't talking up his Star Wars past, instead emphasizing his theater work.
"What's your problem?" he says she told him. "I am Princess Leia. You're Luke Skywalker. Get used to it."
"The Last Jedi" opens on Dec. 15.
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