The opening crawl reveals: War! The Republic is crumbling under attacks by the ruthless Sith Lord, Count Dooku. There are heroes on both sides. Evil is everywhere. In a stunning move, the fiendish droid leader, General Grievous, has swept into the Republic capital and kidnapped Chancellor Palpatine, leader of the Galactic Senate. As the Separatist Droid Army attempts to flee the besieged capital with their valuable hostage, two Jedi Knights lead a desperate mission to rescue the captive Chancellor....
The time period is three years following the events of the previous film, at the onset of the Clone Wars after the Clone Army of the Republic had successfully counter-attacked the Separatist Droid Army of Sith Lord Count Dooku. The two sides in the conflict are the Republic and the Federation.
The Republic is backed by a Clone Army, and led by Supreme Chancellor Palpatine of the Galactic Senate on the planet of Coruscant, while supported by the Jedi Council and its Knights (including Yoda, Mace Windu, Obi-Wan, and Anakin Skywalker). The Federation (or Confederacy) of Independent Systems, is led by Sith Lord Darth Tyranus (or Count Dooku), and supported by the Separatist Droid Army and its evil cyborg military leader General Grievous.
As the film opens, General Grievous of the Separatist Droid Army has infiltrated the Republic's planet of Coruscant and kidnapped Supreme Chancellor Palpatine (Ian McDiarmid). A major space battle is in progress: the Republic's forces of Jedi Knight Obi-Wan Kenobi (Ewan McGregor), a General, accompanied by his former apprentice (Padawan), now Jedi Knight Anakin Skywalker (Hayden Christensen), are fighting against the Separatist Droid Army and its flagship Armada, led by cyborg military commander General Grievous (Matthew Wood).
Their challenging mission is to rescue the kidnapped Supreme Chancellor held on the command ship (The Invisible Hand) as it is escaping from. Buzz droids scamper over the wings of both of their starship fighters, threatening to destroy their controls. Kenobi's interceptor is damaged and his astro-mech R4-P17 is destroyed. Anakin's efforts to blast the buzz droids off his partner's wings fails, although he is able to maneuver one wing to knock most of the droids off.
One of them crosses over to Anakin's fighter, where R2-D2 disables it by hitting its center eye. After Anakin knocks out the shield generator, their two ships crash-land in the command ship's docking hangar bay, where they emerge with lightsabers to take on a group of Battle droid foes. The two decide to "spring the trap" that they knew awaited them, then counter-attacked Destroyer droids and more Battle droids on their way to General Grievous' quarters.
R2-D2 helps them navigate in an elevator, while he simultaneously incinerates two Battle droids in the hangar. As the two Jedi are about to rescue captive Chancellor Palpatine, Count Dooku confronts them and they commence lightsaber dueling. Dooku uses his Force powers to hurl Obi-Wan against a far railing and knocks him unconscious, and then drops a platform onto him.
As he alone faces Anakin (who claims he has doubled his powers), Dooku taunts him: "Good. Twice the pride, double the fall." He also realizes a change in Anakin: "I sense great fear in you, Skywalker. You have hate. You have anger. But you don't use them." Incensed by Dooku's words, Anakin connects with his "dark side" and severs the Count's hands. From the side, Palpatine urges: "Kill him now...Do it" - to which Anakin answers as a Jedi: "I shouldn't" - but decapitates the unarmed and defenseless Dooku anyway.
Palpatine congratulates him on his well-fought victory. As Anakin attempts to depart the ship with the rescued Palpatine and an unconscious Obi-Wan on his back, the Star Destroyer Guarlara blasts and attacks General Grievous' command ship The Invisible Hand. Explosions rock the ship, and it begins to wildly careen in space, and uncontrollably drop in orbit toward Coruscant.
Grievous is able to have his bridge crew stabilize and level out the ship by firing the emergency booster engines, and then captures his three opponents in a ray shield trap. They are apprehended by Battle droids and brought to Grievous' bridge as prisoners, where the General quips: "That wasn't much of a rescue." R2-D2's maneuverings soon allow them to retrieve their lightsabers and duel against Grievous' tall IG-100 MagnaGuards and other droids.
With the two Jedi surrounding him, the clever General uses a guard's electro-staff to smash a window. Drawn out into space, he latches himself onto the hull of the ship with a tow cable, enters one of the ship's escape pods, devilishly launches all the other escape pods as decoys, and then 'abandons ship' by heading in his pod to the Trade Federation's battleship.
Anakin pilots the falling, burning and disintegrating flagship and is forced to crash-land it on Coruscant. It makes a hard, emergency landing on one of the planet's industrial landing platforms, with coordinated directions provided by emergency fire-ships taking the vessel in. Obi-Wan sighs: "Another happy landing." Anakin receives all the praise from Coruscant's politicians in the Republic's executive greeting area for his heroics in saving Obi-Wan from Buzz Droids, killing Count Dooku, and rescuing the Supreme Chancellor.