Palpatine is confirmed to return in Star Wars: The Rise of Skywalker - but he can't possibly be a Force Ghost. The first trailer for Star Wars: Episode IX ended with the evil laugh of Emperor Palpatine, confirming that the greatest Sith Lord of all time has returned to plague the galaxy. It's a satisfying way of ending the sequel trilogy, creating a continuous narrative that runs through the prequels, the original trilogy, and now the sequels; they are all the story of the battle between the light side and Palpatine himself.

Naturally, this shocking revelation is causing Star Wars fans to revisit all the tie-in novels and comics, looking for any hints as to how Palpatine has returned and what his true goal is. They're finding a surprising number of clues, supporting Lucasfilm president Kathleen Kennedy's insistence that this had been the plan all along; the most explicit reference is in the "Aftermath" trilogy of novels, where one of Palpatine's old aides insisted that his Master would rise from the dead.

Related: Star Wars Canon Already Revealed That The Emperor Survived Return Of The Jedi

But just how has Palpatine survived? One common theory doing the rounds is that the Emperor could be a Force Ghost. After all, so the argument goes, in the trailer for The Rise of Skywalker Luke says nobody is ever really gone, suggesting there's a parallel between his own continued presence and the Emperor's return. Here's why that theory can be discounted.

The Rules Of Force Ghosts (And Who Became One In Star Wars Canon)

The idea of Force Ghosts runs all the way back to 1977, when Darth Vader confronted Obi-Wan Kenobi on the Death Star. "If you strike me down," Kenobi famously warned, "I shall become more powerful than you can possibly imagine." Proving the point, Kenobi's body vanished at the moment of his death, and from that moment on his spirit served as a guide to Luke. He had become one with the Force, a spirit that retained its sense of consciousness after death. Viewers could be pardoned for initially assuming that this happened to any Jedi, and yet logically even at this stage it was clear that couldn't be the case; Vader had killed countless Jedi, but was visibly taken aback at what happened to Kenobi at the moment he struck the killing blow.

The prequels have revealed that Qui-Gon Jinn was the first Jedi in a long time to retain the knowledge of how to live on after death. An unusual Jedi, Qui-Gon was humble enough to assume other Force traditions could teach him important lessons, and he learned the trick from a Shaman of the Whills. As confirmed in The Clone Wars, he was killed before he could complete his training, and initially could only communicate with the living world as a disembodied voice. Qui-Gon was able to continue his training after death, and - according to the recently-published anthology book From A Certain Point of View - he eventually learned how to manifest as a Force Ghost. Only a handful of beings have learned this secret: Qui-Gon Jinn, Obi-Wan Kenobi, Yoda, Anakin Skywalker, and Luke Skywalker. The body dissolves at the point of death if the Jedi has completed their training, explaining why neither Qui-Gon's nor Anakin Skywalker's faded away.

Related: Star Wars Reveals Why Qui-Gon Jinn Wasn't On The Jedi Council

From A Certain Point of View contains a short story called "Master and Apprentice," by Claudia Gray, that is actually told from the perspective of the Force Ghost Qui-Gon. It revealed that Force Ghosts transcend time and space, and can see past, present, and future all woven together as one. Meanwhile, Star Wars: The Last Jedi has confirmed just how powerful a Force Ghost can be; decades after his death, Master Yoda had learned to manipulate the physical world when he destroyed the ancient library of Ahch-To.

Page 2 of 2: How Light Side & Dark Side Force Users Can Survive Death

Star Wars Original Movie Force Ghosts

Why Force Ghosts Are Exclusive To The Light Side

The list of Force Ghosts immediately makes it clear that this power is associated with the light side of the Force, and there's a simple reason for it; adherents of the light side of the Force submit to the will of the Force, whereas dark siders attempt to control the Force and drive events in accordance to their own will. In order to live on after death, a light sider has to submit completely to the Force, even to their own imminent demise. A standard dark sider is incapable of doing this, and a Sith even more so.

Matt Stover's novelization of Revenge of the Sith made this pretty explicit. Stover worked closely with George Lucas himself on the script, and was given permission to amplify many of the scenes. As a result, he extends the conversation between Qui-Gon's Force Ghost and Master Yoda to include a longer discussion of immortality. "The ultimate goal of the Sith, yet they can never achieve it," Qui-Gon explained. "It comes only by the release of self, not the exaltation of self. It comes through compassion, not greed. Love is the answer to the darkness." While this book's canonicity can be disputed, the same point was made - albeit less explicitly - in The Clone Wars season 6, which featured a number of episodes dedicated to Yoda's quest for this ability.

How Sith CAN Survive Death

Star Wars - Emperor Palpatine

And yet, Qui-Gon's insistence that the Sith cannot manifest as Force Ghosts seems to sit uncomfortably with another scene in Revenge of the Sith. Attempting to seduce Anakin with the lure of the dark side, Palpatine tempts him with the tale of Darth Plagueis the Wise, a Sith who had learned how to conquer death. The future Emperor doesn't spell out what this means, let alone how to achieve this through the dark side, but it's clear he believes it. In the novelization, the dialogue goes a step further, with Palpatine suggesting that Plagueis' apprentice - i.e. himself - may well be "virtually immortal."

Related: Star Wars 9 Theory: Palpatine Never Existed, It Was Always Darth Plagueis

In the old Expanded Universe, a Sith could survive death by transferring their essence into a nearby body, a relic of some kind, or even into a geographical location. In the first case, anyone who is close to a dying Sith can actually be possessed by them; in the second, a Sith can implant their consciousness in an object such as a mask, and continue to exert an influence through this relic; and in the third, the Sith spirit can be bound to a specific place and essentially "haunt" it. While Lucasfilm has abandoned the old Legends continuity, the Force powers don't seem to have changed much. The Clone Wars season 6 included arcs in which Sith spirits were seen inhabiting a specific site, while Charles Soule's recent Darth Vader comic introduced Lord Momin, a Sith heretic whose spirit had inhabited a mask. Clearly this power seems to have been retained in the new canon.

The key point is that a Sith spirit can indeed survive after death - but it doesn't seem to be a pleasant experience. Where a Jedi Force Ghost experiences death as freedom and empowerment, a Sith appears to be bound to a new cage - be it another person's body, a relic, or a place. That's a far cry from the kind of life after death Palpatine described to Anakin Skywalker in Revenge of the Sith, and certainly not something Palpatine would accept as his final future state. So, while Palpatine can't be a Force Ghost, it's also unlikely that the key is in an essence transfer - unless that was merely a step along the journey to a more effective solution.

More: Star Wars: The Rise Of Skywalker Trailer Breakdown - 28 Story Reveals & Secrets

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