Master Mace Windu preparing to execute Palpatine, who is revealed to be the Sith lord Darth Sidious, in his office. Anakin, who believes Palpatine can help him, intervenes and duels Windu, who attempts to fight off Anakin before returning to finish off the chancellor. Anakin stabs him and throws him out a window to his death; Palpatine then takes Anakin under his wing, dubs him "Darth Vader", and orders him to wipe out all of the Jedi in the Jedi Temple. Darth Vader and an army of clone troopers make their way to the Temple, where he kills librarian Jocasta Nu, initiating the massacre. While the clones mop up the survivors, Vader confronts Serra Keto and crushes her with a pillar. He is then confronted by her master, Cin Drallig, whom he also duels. The two wind up outside of the temple, where Vader impales Drallig through the chest. Across the galaxy, the clones, following orders from Palpatine, turn on their Jedi allies and murder them. Obi-Wan manages to escape from Utapau after being relentlessly hunted by both the droids and his own soldiers. Palpatine orders Vader to go to Mustafar and wipe out the Separatist leaders to eliminate all potential threats to his rule. After brutally cutting down their Neimoidian guards, Vader forces his way into the council chambers, killing Poggle the Lesser, Wat Tambor, and two others as Viceroy Nute Gunray flees for his life. Vader cuts down Gunray's lieutenant Rune Haako, and then catches Gunray trying to escape on his ship, which he destroys and tosses into the planet's lava. Meanwhile, on Coruscant, Obi-Wan & Master Yoda raid the ruins of the Jedi Temple, clearing it of clone soldiers and deactivating a beacon left by them as a trap for other Jedi. Desperate to know who was responsible, Obi-Wan discovers security recordings of Anakin becoming a Sith lord. The recording also reveal Vader's location, so Obi-Wan heads to Mustafar to confront him. The two former friends engage in a ferocious lightsaber duel across the Mustafar facility, which is slowly being destroyed by lava. The two end up on a platform floating down a lava river; Obi-Wan jumps off and demands that his fallen apprentice surrender. An enraged Vader leaps over him, allowing Obi-Wan to slice off his legs and left arm. Vader slides towards the lava and catches on fire; Obi-Wan picks up his fallen lightsaber and