Ian McDiarmid returned as Emperor Palpatine in The Rise of Skywalker, where the character was revealed as the one pulling the strings behind the sequel trilogy, yet Palpatine met with a pretty definitive ending when he was defeated by Rey.
That doesn’t mean that Palpatine is done in Star Wars, however. Those stories just might be set before the events of that film.
There’s nothing definitive here, but it’s possible that he could even return sooner than later. In a recent interview with Metro, McDiarmid acknowledged his character’s ending yet left the door open for a potential return in some other way. “I think I have to accept that, thanks to my ungrateful granddaughter [Rey Skywalker], my annihilation was finally final,” McDiarmid said. “[But] of course [Darth] Vader is back in the new [Obi-Wan Kenobi] television series, so I suppose it’s not impossible that one day his mentor might be discovered once again skulking in the shadows.”
McDiarmid, like Star Wars fans, doesn’t expect Palpatine to return once again, surviving another death moment on-screen, and that’s a good thing (also, the fact that he answers the question like he’s actually Palpatine is great). But he then mentions the return of Darth Vader as evidence that perhaps Palpatine can return too… and people can’t help but wonder if that is a hint that maybe Palpatine is going to be in the Obi-Wan Kenobi series.
We haven’t heard any rumors of that happening, but that certainly doesn’t mean it won’t happen. I’d guess that McDiarmid would have interest in returning to the character again, and him appearing in the Kenobi series in a cameo role talking with Lord Vader via hologram or something like that would seem to be a really natural fit. Some of the concept art for the series actually showed Vader sitting on his throne in his castle on Mustafar talking with someone via hologram, so it would fit well. If it was supposed to be Palpatine he was speaking to in these images he’d probably be kneeling before him like we see in other moments, but it’s not a far stretch to think that this could be adapted for a different moment on-screen.
So let’s be clear that there’s nothing actually reporting that McDiarmid is going to be in Obi-Wan Kenobi, so don’t get your hopes up that it’ll be happening. However, him leaving the door open for a potential return, and specifically mentioning Vader’s return in this upcoming series, does seem to raise that intrigue ever so slightly.