Star Wars: The Rise of Skywalker brought back Emperor Palpatine, but the film didn't do an excellent job of explaining how that was possible - and so, fans have to rely on the Visual Dictionary to fully understand how he returned. Palpatine was assumed to be dead following the events of Return of the Jedi and wasn't really a factor in the sequel trilogy before its final installment. So naturally, the public was intrigued with his involvement in the latest narrative.
Marketing for the movie intentionally revealed very little about his return, but director J.J. Abrams justified it by pointing out how Star Wars: The Last Jedi, he had been in the thick of things as the being manipulating events behind the curtain as he's the secret grandfather of Rey (Daisy Ridley). With that reveal, The Rise of Skywalker somehow justified Palpatine's involvement, though it did a bad job with was explaining how he's able to return.
In the film, we find out that he'd been hiding in Exegol all along, while Supreme Leader Snoke's (Andy Serkis) physical body housed his consciousness. However, it didn't get into specifics on how he even got to the remote planet. Fortunately, the Star Wars: The Rise of Skywalker Visual Dictionary provided additional details in the hopes of properly clearing out this seeming plot hole. According to the tie-in book, Darth Sidious was brought to Exegol by his hooded cohorts called the Sith Eternals (via Digital Spy). These mysterious beings weren't mentioned in the movie, although they were explicitly featured during the climactic battle between Rey and her grandfather. Apparently, they are devoted Sith followers who were Palapatine loyalists. After Darth Sidious' defeat in Return of the Jedi, they brought him to Exegol, and using "technology and occult," they were able to revive him.
Abrams can argue that there's simply not enough screentime to get into the specifics of Palpatine's resurrection. However, even with the additional information from the Visual Dictionary, there are still aspects of the his return that remain unclear. While it did mention on how the Sith Eternals were able to resurrect him, it's so vague that it could be anything. It's an understatement to say that The Rise of Skywalker had its work cut out for it. Aside from the string of subplots that needed addressing, it also had to work around General Leia Organa's personal story unfinished. However, since bringing the Emperor back at the Star Wars forefront was supposed to be integral to the whole sequel trilogy, glossing over it would obviously draw some backlash from fans which has become the case.
It's curious if Lucasfilm will eventually clarify this glaring plot hole given that this has become a favorite topic of conversation among fans. Perhaps a future novel can further delve into what really happened to the Emperor leading to his appearance in Star Wars: The Rise of Skywalker. Maybe, even the Sith Eternals can be the focus of an book so we can fully understand their origins and potential future in the franchise. But at this point, these are the only official details given regarding the matter.
More: Star Wars: The Rise of Skywalker - Palpatine's Plan & Sith Ritual Explained
