George Lucas plot twist, c. 1980: The dark-cloaked inhuman villain of Star Wars, the evil being who struck down Obi-Wan Kenobi with his blood-red Sith blade, the ruthless blackheart who killed his officers for failure and pursued the Rebels around an entire galaxy...is Luke Skywalker's father.
George Lucas plot twist, c. 1998: The queen disguises herself by taking off all of her makeup and attending to her stand-in, as though she is not the queen.
George Lucas plot twist, c. 1982: The Rebels gather every available capital ship and commence an attack on a half-finished Death Star...and it turns out their spies were permitted to learn the coordinates of the new DS and the shield deactivation code just so the Emperor could set up a trap and painfully reveal that the superlaser on the DSII is fully operational.
George Lucas plot twist, c. 1998: The Sith mastermind behind the Trade Federation blockade of Naboo is Senator Palpatine with a cloak pulled over half his face. Innumerable Jedi living on the same planet can't even begin to figure this out.