"I happen to know that George didn't kill Luke until the end of [Episode] IX, after he trained Leia," Hamill told IGN. "Which is another thread that was never played upon [in The Last Jedi]."
Leia, Luke's sister, was trained as a Jedi Knight in the since-discarded canon of the original Extended Universe. Hamill's revelation marks the first time it was learned Lucas originally intended to close the episodic Skywalker Saga with Luke's death.
Star Wars: The Last Jedi writer-director Rian Johnson killed Luke by its end, the disillusioned Jedi spawning a Force-projected version of himself across the galaxy to rescue the last remaining Resistance fighters huddled on the planet Crait. Among those saved was General Leia, who got to bid farewell to her long-missing brother before his heroic move left him physically extinguished.
Exhausted, Luke died with peace and purpose in front of twin suns and faded away into nothing — leaving just robes behind.
"George had an overall arc – if he didn't have all the details, he had sort of an overall feel for where the [sequel trilogy was] going – but this one's more like a relay race," Hamill said of the Sequel Trilogy, which was first marked out by J.J. Abrams and Lawrence Kasdan for The Force Awakens before being handed off to Johnson. "You run and hand the torch off to the next guy, he picks it up and goes."
Jurassic World director Colin Trevorrow was to succeed Johnson and helm Episode IX, but he was fired following conflicts with Lucasfilm. Abrams was then recruited to close out the trilogy he helped establish.
"Rian didn't write what happens in IX – he was going to hand it off to, originally, Colin Trevorrow and now J.J.," Hamill said. "It's an ever-evolving, living, breathing thing. Whoever's onboard gets to play with the life-size action figures that we all are."
During an appearance on ABC's Good Morning America, Hamill answered it's "probably fair to say yes" when asked if Luke would be returning from beyond the Force come Episode IX, which heads in front of cameras this summer.
Hamill told Radio Times he and Abrams "haven't really discussed it," adding Luke's fate is ultimately "in J.J.'s hands," explaining he'd like to see the Jedi Master return from the grave as a frightening Force ghost.
Star Wars: The Last Jedi is now available to own digitally and is available to own on 4K Ultra HD, Blu-ray and DVD March 27.