After the sluggish and superfluous Phantom Menace and Attack of the Clones, writer-director George Lucas finds his lightsaber once again for this dramatically cogent and highly satisfying finale to the Star Wars saga. As the intergalactic republic crumbles and the dictatorial Sith prepare to take command, Jedi knight Anakin Skywalker (Hayden Christensen) is sorely tempted by a malevolent conspirator who promises him unlimited power if he'll yield to the dark side of the Force. Lucas's understanding of democracy and fascism isn't exactly subtle, nor is his characterization of Anakin, but the two are so perfectly fused as part of an action plot that the movie plugs into the same mythological wall socket that powered the original Star Wars. With Ewan McGregor, Natalie Portman, Ian McDiarmid, Samuel L. Jackson, and Christopher Lee. PG-13, 140 min. Reviewed this week in Section 1. Burnham Plaza, Century 12 and CineArts 6, Chatham 14, Crown Village 18, Davis, Ford City, Gardens 1-6, Golf Glen, Lawndale, Lincoln Village, Norridge, North Riverside, Pickwick, River East 21, 62nd & Western, Village North, Webster Place.