Although die-hard fans expected to be blown away by the teaser trailer for Star Wars: The Rise of Skywalker, most weren't prepared for the unmistakable cackle of Emperor Palpatine that closed out the footage, or for the appearance by actor Ian McDiarmid on the stage at Star Wars Celebration Chicago. Since then, the franchise faithful have been let to speculate how the villain survived the events of 1983's Return of the Jedi. However, his return was foreshadowed 28 years ago.

Although the Expanded Universe, now known as Legends, is no longer canon, it was there Palpatine revealed one of his biggest secrets, in the early-1990s Dark Horse Comics series Star Wars: Dark Empire.

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Many have theorized that, just like a Jedi can appear after death as a Force ghost, so too can the Sith. It's a relatively simple explanation for Palpatine's presence in The Rise of Skywalker. However, we can't ignore Dark Empire, by Tom Veitch, Cam Kennedy and Todd Klein, in which the former emperor is shown to have survived beyond the events of Return of the Jedi, with his essence transferred from his old, decaying body into a clone. Palpatine purportedly experimented for years, transferring his spirit from body to body. According to Dark Empire, his death at the hands of Darth Vader wasn't his first; he'd cheated mortality, through a combination of the Dark Side and technology.

While the Expanded Universe is no longer canon, Lucasfilm has cherry-picked certain segments for the new era of Star Wars. For example, Grand Admiral Thrawn was reintroduced on Star Wars Rebels. So, while it may be unlikely, we can't rule out that director and co-writer J.J. Abrams may want to selectively adapt that process as a means of reviving the Palpatine. Of course, he'd have to do some adjusting of the new trilogy's backstory, with the rise of Supreme Leader Snoke and the First Order, but it's easy to detail Palpatine's resurrection as a process that takes time, and only comes to fruition in the trilogy's finale. It could even be that Luke Skywalker's death was the catalyst for Palpatine's energy to be transferred into his next vessel.

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Some retconning could provide a link to what Palpatine told Anakin Skywalker in Revenge of the Sith, in which he spoke about his life as Darth Sidious,  and trying to learn from his own master, Darth Plagueis, how to cheat death. Even if technology is ruled out, that this procedure is so heavily tied to the Force still makes it applicable to the big screen. Remember, we never saw Force projection in the movies before its introduction in The Last Jedi, so this transference could simply be another power only an expert like Palpatine could wield.

Well before the Expanded Universe was decreed as no longer canon, Lucasfilm's Leland Chee clarified the Palpatine seen in the movies is not a clone, which contradicts Dark Empire. But again, Abrams could fiddle with continuity to facilitate that. What's also intriguing is Palpatine may not require clones in order to transfer his spirit. Dark Empire also illustrated that, once Palpatine has a suitable vessel, he could possess it at will. The villain threatened to use Luke, and then Leia's unborn baby, as a host, which presumably means he could have jumped from body to body following Return of the Jedi, until the right one was found.

The point is, while we didn't assume Palpatine ever had a means of coming back, something influenced by Dark Empire could simply be a contingency we never considered. After all, just like Order 66, the Emperor has always had backup plans -- whether it be for his apprentices, the Republic and its Separatists, or, of course, the Jedi Order. We can easily imagine Sheev Palpatine hiding a Hail Mary pass like this hidden in the folds of his cloak. Would it be out of left field? Certainly. But as we know, the franchise doesn't mind taking risks, and this feels like something Abrams can repurpose and get away with.

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Palpatine has become one of cinema's most iconic tyrants, and fans will be appreciative of him working the system -- whether through technology or mystical means -- to come back. If it's by perverting the Force, it's actually within character because since his days as Sidious, Palpatine desperately clamored to find a gateway to immortality. If Abrams leans into Dark Empire the way we think he might, then the Emperor may have found what he was looking for all this time.

Directed and co-written by J.J. Abrams, Star Wars: The Rise of Skywalker stars Daisy Ridley, Adam Driver, John Boyega, Oscar Isaac, Lupita Nyong’o, Domhnall Gleeson, Kelly Marie Tran, Joonas Suotamo, Billie Lourd, Keri Russell, Matt Smith, Anthony Daniels, Mark Hamill, Billy Dee Williams and Carrie Fisher, with Naomi Ackie and Richard E. Grant. The film arrives Dec. 20.