[LanPB01]

I assumed that Palpatine didn't realize he was possessed (which would explain why the Jedi are so confused as to why they can't detect the presence of the Sith; doesn't explain why they couldn't detect Darth Maul, though), but after the Republic crumbled, the Sith spirit just took control full time.

[Chancellor Palpatine]

I am not possessed. I am a Dark Lord of the Sith, fully aware of all my capabilities.

[roadcat]

"I assumed that Palpatine didn't realize he was possessed (which would explain why the Jedi are so confused as to why they can't detect the presence of the Sith; doesn't explain why they couldn't detect Darth Maul, though), but after the Republic crumbled, the Sith spirit just took control full time."

Time to spice up the movie - a cameo with Michael Jackson playing Darth Barf (no acting necessary, just be himself) who invites the child Palpatine to visit his digs... No fancy explanation after this scene as to why Palpatine is possessed.