Viewers, beware. The Two Towers, the dazzling second installment of The Lord of the Rings trilogy, picks up exactly where the first one left off. No Star Wars-style scroll to bring you up to speed, no quick compilation of scenes from the first film, no opening Cate Blanchett narrationnothing. It begins in medias res, as though you had just stepped out for a few seconds to get more popcorn. If you didn't see last year's The Fellowship of the Ring, Peter Jackson, the trilogy's wizardly director, isn't about to cut you any slack.