You'd think that having been in a fair few of the movies, Harrison Ford might have a passing knowledge of Star Wars lore.
But it appears not. And he's not bothered about learning either.
Spoilers lie ahead for Star Wars: The Rise of Skywalker...
During an interview with USA Today, he discussed his unexpected return to the series in The Rise of Skywalker, despite having been run through with a lightsaber in The Force Awakens.
“When JJ asked me to do it, I said, 'Are you kidding? I’m dead!'” Ford says,
“'Sorta dead. You can do this.' He hadn’t written anything at that time. But he said, 'This is going to be great.' So I said okay. If JJ asked you do something, you’d probably do it too. He’s a very persuasive guy.”
But some fans have questioned whether Solo's return was as a 'Force ghost', and if it was, whether that was, strictly speaking, OK, considering Solo was never particularly interested in or affected by that aspect of Star Wars mysticism.
Asked his opinion on whether Solo was a Force ghost in the movie, he said: “A Force ghost? I don’t know what a Force ghost is.
“Don’t tell anyone. I’m not talking loud enough for your recorder. I have no (expletive) idea what a Force ghost is. And I don’t care!”
Well, he's well out of the whole thing now, so unless he's set to appear in one of the Disney+ Star Wars spin off series, he probably doesn't need to know.
Per Star Wars archive the Wookieepedia, ‘The Force ghost was the soul and essence of a deceased Force-sensitive who denied the will of the Force upon death, yet was able to interact with the living’.
Alec Guinness's Obi Wan Kenobi was the first Jedi to appear as a Force ghost on screen, after he was slain by Darth Vader in A New Hope.
Dozens of others have appeared in the wider Star Wars books and comics, while we've also seen the likes of Yoda, Anakin Skywalker and Luke Skywalker appearing from the other side in the movies.