Mark Hamill Wouldn't Even Tell Carrie Fisher About Star Wars' Biggest Twist

Spoiler alert! In the "Star Wars" franchise, Darth Vader is Luke Skywalker's father. Shocking, isn't it? The secret has been out there for over 42 years now, ever since "The Empire Strikes Back" made its way into theaters on May 21, 1980. But imagine you're Mark Hamill, the actor playing Luke, and director Irvin Kershner and "Star Wars" creator George Lucas have entrusted you alone with the secret.

That's the situation Hamill found himself in while "The Empire Strikes Back" was in production and he was getting ready to film the scene in the cloud city of Bespin, where Luke would lose a hand and the reveal would come. Even David Prowse, the actor who physically embodied Vader on set, wasn't privy to the secret, though back in 1978, before the script for "Empire" was ever written, he had made a remarkably accurate guess about what would happen in the story.

While promoting "Star Wars: The Last Jedi" on "The Graham Norton Show" in 2017 (video below), Hamill discussed what it was like to sit on the Vader-is-Luke's-father reveal while even Harrison Ford and Carrie Fisher, his co-leads in "The Empire Strikes Back," were left in the dark. The actor spoke first about passing the script of the original "Star Wars" movie, retroactively labeled "A New Hope," around freely because no one cared back then and it just seemed goofy. The blockbuster success of "Star Wars" changed everything. Hamill said:

"By the second film, that's when their scrutiny became more intense. And there was a wonderful substitute revelation in that scene. And the way we filmed it, Vader said, 'You don't know the truth. Obi-Wan killed your father.' And the idea of Alec Guinness being the real villain, I thought, wow, what a spectacular twist."

Hamill further recounted to Graham Norton how it all went down when he first learned about Vader being Luke's father. He said:

"Irvin Kershner, took me aside, He came to my dressing room, actually, and he said, 'I'm going to tell you something.' I know it, George Lucas knows it, and when I tell you, you'll know it, but if it leaks, we'll know it was you.' So I said, 'What, what?' And he handed me the piece of paper that said, 'I am your father.' I [was] just shocked. I said, 'Is that true?' He said, 'Well, you search your feelings, we're going to play it like that.' So, oh my gosh, Dad Vader! And then I was paranoid 'cause I thought, you know, it was way before social media and all of that. But I had to keep the secret for about a year and a half. I didn't tell Carrie. Telephone, telegraph, tell Carrie. She had no vault whatsoever."

Hamill added that at the screening for "The Empire Strikes Back," when the reveal came, Ford turned to him and said,  "Hey, kid. You didn't f****** tell me that."

In the 21st century, as the internet has made it easier to proliferate spoilers, filmmakers and studios have often gone to great lengths to conceal the secrets of hotly anticipated movies. Director Christopher Nolan, for instance, has gone so far as to lock actors in a room and not let them leave with their own copy of the script. It would certainly be much harder in today's climate for a film like "The Empire Strikes Back" to guard its secrets on the way to the big screen, but Hamill at least did his part in preserving one of the greatest movie twists of all time.