Handlung

For three years, The Clone Wars have raged across the galaxy, as Republic and Separatist force fight for dominance. The Droid leader General Grievous sweeps into the Republic capital and kidnapped Chancellor Palpatine, leader of the Galactic Senate.

Orbiting above Coruscant, Jedi Master Obi-Wan Kenobi (Ewan McGregor) and Knight Anakin Skywalker (Hayden Christensen) lead a mission to rescue Supreme Chancellor Palpatine (Ian McDiarmid) from the cyborg Separatist commander General Grievous (Matthew Wood). The Republic armada engages in battle with General Grievous' endless battleships. Obi-Wan and Anakin commandeer 2 smaller ships and try to sneak in between the 2 battle groups.

After infiltrating Grievous' flagship, Obi-Wan and Anakin battle the Sith Lord Count Dooku (Christopher Lee). Count Dooku was the second apprentice of Darth Sidious, the Dark Lord of the Sith, whose plan to conquer the galaxy relied on Dooku leading a pan-galactic secessionist movement against the Republic. As such, Dooku immersed himself in the dark side of the Force and worked tirelessly to advance his and his master's Grand Plan while being unaware that he was merely a pawn of his master, who viewed him as no more than an expendable piece in his plan. Dooku manages to get the better of Obi-Wan, but Anakin battles him and cuts off his hands. Palpatine orders Anakin to decapitate Dooku.

Palpatine wanted to leave Obi-Wan behind saying there is no time, but Anakin insists on taking him along while Obi-Wan was unconscious. Meanwhile Grievous' flagship is heavily damaged in the battle with the Republic ships. The three attempt to escape the ship, before Grievous finds out where they are, and captures them. Bringing them to his ship's bridge, the Jedi creates a diversion, causing Grievous to flee his ship, but also jettison all the escape pods. Grievous then orders his heavily damaged ship to be rammed into the planet, as he knows that Palpatine and the Jedi have no way to escape.

As the ship begins to plummet into the planet's upper-atmosphere, Anakin attempts a daring crash-landing, that manages to get them back onto the planet, rescuing the Chancellor. Palpatine considers Anakin to be his hero. Palpatine informs Windu that Grievous has escaped and the Clone wars continue in his absence. Windu assures Palpatine, that the Jedi will find Grievous to bring the war to an end.

Grievous is instructed by Lord Sidious to move all separatist leaders to Planet Mustafar. Sidious says that count Dooku's death was a necessary loss and assures Grievous that soon he will have a new apprentice, one far younger and more powerful.

Anakin reunites with his wife, Padmé Amidala (Natalie Portman), who tells him she is pregnant. Anakin has visions of Padmé dying in childbirth and the fears of how he was unable to save his mother resurface. Seeking council from Jedi Master Yoda (Frank Oz), Anakin is unwilling to take the master's advice to not develop strong attachments, lest greed led him to The Dark Side of the Force.

Palpatine appoints Anakin to the Jedi Council as his representative. Such an appointment would automatically make Anakin a Jedi Master, but as the council did not make this decision, they reach a compromise: Anakin may sit on the council per the Chancellors wishes, but not be given the rank of Master, leading to Anakin becoming angered at this decision.

Oni-Wan says that the Jedi council does not trust Palpatine and believes that he is trying to interfere in Jedi affairs through Anakin. They instead instructed him to spy on Palpatine, diminishing Anakin's faith in the Jedi. Anakin grows even more upset when Padme claims she feels the Republic is growing more corrupt and asks him to talk to the Chancellor to help end the war and resume diplomacy.

Anakin is called to the Coruscant Opera House for a private meeting with the Chancellor, who tells him that they have found General Grievous and the Separatist leaders hiding on the planet Utapau. Palpatine then requests Anakin to sit with him, and confides in Anakin, that he believes the Jedi want to overthrow him, and take over the Republic. Anakin attempts to defend the Jedi but finds himself conflicted.

It is then that Palpatine starts telling Anakin about a Sith legend, revolving around Darth Plagueis the Wise, who could use the powers of the Dark Side to save people from dying. This catches Anakin's attention, but Palpatine warns Anakin, that such powers cannot be wielded by a Jedi.

Meanwhile, on Utapau, Grievous relocates the Separatist leaders to the volcanic planet Mustafar. Yoda knows that capturing General Grievous will end the war and will be the first step in removing the emergency powers granted to the Chancellor and restoring them to the Senate. Obi-Wan travels to Utapau, where he confronts and kills Grievous, while Yoda (Frank Oz) travels to the Wookiee planet of Kashyyyk to defend it from the Separatist droid attack.

Anakin is asked to inform Palpatine of the impending victory over the rebel armies. Palpatine reveals that his mentor taught him everything about the Force, and even the nature of the Dark Side. Palpatine says that only through him can Anakin achieve a power far greater than the Jedi. He says that by learning the Dark Side of the force, Anakin would be able to save the life of his wife. The chancellor then reveals to Anakin that he is a Sith Lord. However, given what Palpatine has told him, Anakin is unable to bring himself to strike down Palpatine, feeling he knows how to save Padme.

Anakin then returns to the Jedi Temple, only to find that Obi-Wan has killed Grievous, and Mace Windo and other Jedi are going to make sure that the emergency powers the chancellor has, are returned to the Senate. Anakin realizes that Palpatine is the Sith Lord behind the Clone Wars and reports his treachery to Mace Windu (Samuel L. Jackson). Windu did not want to take Anakin for the confrontation as he sensed a great deal of confusion in him, but Anakin insisted that he should go.

Windu confronts and subdues Palpatine, leaving the latter disfigured. Anakin attempts to stay calm but figures the Jedi will kill Palpatine and with him, will go the secret to keeping his wife alive.

Desperate to save Padmé, Anakin prevents Windu from killing Palpatine by slicing off his right hand. Palpatine then sends Windu falling to his death. Anakin is unsure what to do, until Palpatine requests he become his apprentice and learns the powers of the Dark Side. Anakin pledges his service to the dark lord, and is then 'knighted,' as Darth Vader.

Palpatine issues Order 66, which commands the clone troopers to kill their commanding Jedi generals across the galaxy, while Vader and a battalion of clone troopers kill the remaining Jedi in the Jedi Temple. Anakin is then tasked with destroying those in The Jedi Temple, before going to Mustafar, to destroy the Separatist Leaders and end the war.

Vader then travels to Mustafar to assassinate the Separatist leaders, while Palpatine declares himself Emperor before the Galactic Senate, transforming the Republic into the Galactic Empire. He denounces the Jedi as traitors.

Once his dark deeds are finished, Anakin goes to Padme, claiming he saw Mace Windu attempt to kill Palpatine, and claiming that his allegiance now lies with the Chancellor. He then tells Padme he must go to Mustafar, and intends to end the war, once and for all.

Senator Bail Organa (Jimmy Smits) happens to see the temple attack but is turned away by clone troopers. As he is about to leave, he sees a young Jedi attempting to fight them off, before the troopers kill him. Escaping from the temple, Organa is concerned for the Jedi, and going aboard his ship, heads off into space to see if he can find others who have survived the purge.

Obi-Wan and Yoda survive Order 66 and learn that Anakin has turned to the dark side. Yoda claims a retreat signal is also being broadcast from the Jedi Temple, and Obi-Wan recommends they go back there to stop it, to keep any other Jedi from returning and being killed.

Upon their return to Coruscant, Bail is requested to attend an emergency meeting of the Congress. While the Yoda and Obi-Wan sneak off to the temple, Bail meets with Amidala in the Senate, where the two hear Palpatine declare that 'the Jedi rebellion has been foiled,' after they attempted to overthrow the Senate. Promising to wipe out every remaining Jedi, Palpatine then declares that the Republic will now be re-organized into the First Galactic Empire, much to the horror of Padme and Bail, but to thunderous applause from those around them who believe the Emperor's lies.

Back at the temple, Obi-Wan finds security hologram footage and is shaken when he sees Anakin has committed these acts, pledging his fealty to Palpatine. On Coruscant, Yoda instructs Obi-Wan to confront Vader while he faces Palpatine. Obi-Wan seeks Padmé to discover Vader's whereabouts and reveals his treachery. Padme is unwilling to believe the claims that her husband has turned to the Dark Side and that Palpatine is behind everything including the war. Padmé travels to Mustafar, unaware that Obi-Wan has stowed aboard her ship, and pleads with Vader to abandon the dark side. Anakin claims Obi-Wan is lying, and that he is now powerful enough to not only protect her, but powerful enough that the two of them can rule the galaxy. When Obi-Wan emerges, an enraged Vader believes Padmé has betrayed him and strangles her.

Obi-Wan and Vader engage in a light-saber duel. The duel between Anakin and Obi-Wan takes them through the Separatist's hideout, then out onto a river of lava. Obi-Wan force jumps onto a nearby bank. When he claims Anakin should not follow, the Sith Apprentice refuses to back down, and attempts to jump over the Jedi. Kenobi takes the chance to slice at Anakin, cutting off his limbs, and sending him tumbling down to the edge of the lava river. Vader is then burned alive by a nearby lava flow as Obi-Wan retrieves Vader's light-saber and leaves him dead.

Meanwhile, Yoda battles Palpatine on Coruscant, culminating in a stalemate. Yoda realizes the Sith Lord is too powerful to overcome. Using a comm-link, Yoda calls for Bail to come to the Senate, and the Jedi Master is saved, but sadly feels he has failed to stop the Sith. Yoda flees with Senator Bail Organa (Jimmy Smits) and regroups with Obi-Wan and Padmé on the Planetoid Polis Massa. Padmé gives birth to twins, whom she names Luke and Leia. She dies soon after, still believing there is good in Anakin.

Sometime later, having sensed that his apprentice was in danger, Palpatine arrives on Mustafar. The apprentice is then taken to an Imperial medical facility on Coruscant, where the painful task of trying to save Anakin begins. On Coruscant, Vader's mutilated body is treated and encased in a black, armored life-support suit. When he asks about Padmé, Palpatine says Vader killed her out of rage, leaving Vader devastated.

Obi-Wan and Yoda conceal the twins' birth from the Sith and retreat into exile until the Empire can be challenged. As Padmé's funeral is underway on Naboo, Palpatine and Vader supervise the construction of the Death Star. Bail takes Leia to Alderaan to raise her as his daughter. Obi-Wan delivers Luke to his step-uncle and step-aunt, Owen and Beru Lars, on Tatooine. Obi-Wan settles nearby as a recluse while watching over young Luke.

On Bail's ship, he also leaves C-3PO and R2-D2 in the care of the ship's Captain, telling the loyal crew member to have the protocol droid's mind wiped.

On Naboo, a massive funeral is held for the former Queen.

On a Star Destroyer, the Emperor and Vader are now supervising the early stages of a super-weapon, called The Death Star.

On Alderaan, Bail returns to his wife, and hands her their new, adopted daughter.

On Tatooine, Obi-Wan hands Luke over to his uncle and aunt. As he walks off into the desert, the young couple stare at the twin suns rising over their homestead.