"It was certainly unexpected — I already had a beginning, middle and end; I never thought we'd come back," he told the BBC on the red carpet of filming Episode VII. "To go on to those sets that evoked so many memories, it is just astonishing."

While Hamill noted that he wasn't on set when franchise co-star Harrison Ford injured his ankle, he said, "It was really terrible, but I hear he's doing really well. It will take more than that to stop Harrison Ford!"

Still, he called it "fantastic" to reprise the original George Lucas trilogy's roles alongside Ford and Carrie Fisher. "I thought even if they did a third trilogy, we wouldn't be involved, because it is really about the new generation of characters. We are just there to lend our support and grow contractually obligated beards," he joked.

What does he think of J.J. Abrams' new recruits? "They are so talented. They are all so diverse — there are people I recognize, like Andy Serkis, and new people that I've never seen before, like Daisy Ridley. But they are so good. I'm thinking of asking them for advice; I don't want to give any myself!" he said.

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"It's one of the first Cons I've missed in years," he added of missing this year's San Diego meetup. "I'm a comic book nerd myself so I miss all you guys! Hopefully I'll be back next year."

Email: Ashley.Lee@THR.com

Twitter: @cashleelee